I had a short bed Sherline lathe and found the combination of not being able to slide the tail stock off the end of the bed and the extra steps needed to remove the tail stock a real irritation. Because of the work I was doing at the time, clock and watch restoration, a flex shaft was used a lot when repivoting and polishing small bits and pieces. The tail stock was always in the way, but was always needed for the steps prior to needed the flex shaft. This may not be something that effects most folks, but it was an issue for me. The quite limited between centers distance also required the use or fabrication of quite short tools for use in the tail stock chuck.
I have both Taig and Sherline lathes, and did replace the Sherline short bed with a long bed. The Sherline has the added benefit / curse of moving the carriage via lead screw with no quick movement option. Given 20 turns per inch, having to turn the knob 200 times to move 10 inches sort of sucks, but being able to turn a 0.047 inch step to a shoulder dead on without multiple measurements and test fits is a joy.
Before we continue, please know that I still have these machines now that I've retired. I just used the Taig to make some bushings for a family tall case clock and still found it a nice experience. The Sherline is used for some model making when having all the movements controlled with graduated dials is beneficial. These are both very good machines, but are coming from quite different design philosophies. Sherline was build to be a fairly complete and good looking system of machines and accessories. Taig originated in the idea that everyone should be able to afford a basic simple metal lathe, to the point of selling it in kit form. I think I saw the original Taig lathes being demoed at one of the Timonium Hamfests back in the late 70's / early '80's so amateur radio equipment builders could make all the weird fiddly little parts needed. I like them both, use them both, and just can't get into a fanboy sort of view towards one over the other.
The Taig VS Sherline question is a recurring theme in many forums and groups. Here's something I wrote maybe 10 years ago on a clock forum, not much has changed in my view but a few updates are incorporated:
The Sherline lathe has the following pluses:
1) Larger through hole in spindle, MT1 spindle nose, good WW adapter for spindle.
2) Better 3 jaw chuck . You can use a sherline chuck on a Taig with a spacer ring or by turning down the register on the Taig spindle.
3) A leadscrew so hand cranked single point threading is an option. While in these sizes, taps and dies are usually preferable to single point work, things like optical adapters and other large diameter fine thread work needs a single point approach unless you are doing thread milling in the CNC world. The Sherline threading adapter is a real pain in the rear Rube Goldberg / Heath Robinson deal, but it works and is sometimes the only way to get a job done. You will grumble while getting it all set up, but you will get some results...
4) A wonderful smooth variable speed motor and controller.
5) A short MT0 tail stock as opposed to the Taig threaded tail stock with hard center.
6) Sherline does sell several different spindles / head stocks these days. Just consider the cost of a complete head stock assembly includes the motor, speed controller, and motor mounting hardware. Swapping head stocks means either buying an expensive complete assembly or moving the motor and speed controller between head stocks.
7) The head stock can swivel. Rarely needed, but sometimes just the thing for putting on a taper without using the silly low profile bass-akwards "compound" accessory. And yes, look at it and you'll see why the quotes are used. The Taig compound isn't really much better, just the larger swing gives a wee bit of useful breathing room if you HAVE to use it.
Things that irk me about the Sherline:
1) Biggest thing for me - you can't remove the tail stock easily. With a long bed you can slide it far enough to be out of the way. On a short bed it's often in the way.
2) Smaller work envelop than the Taig. Some stuff that fits the Taig easily is a pain on Sherline.
3) Silly expensive accessories.
4) Steady rest is unusable as delivered, you have to work the brass bars into a usable configuration and the cast frame is silly thick and bulky. A nit perhaps, but you look at the thing and you wonder what on earth they were thinking. The Taig steady is ugly maybe, but it works.
5) Not really made to easily reconfigure. If you do odd stuff, the Sherline doesn't make it easy to just bolt on a hunk of stuff where you need it for a rest, fixture, or a stop.
Things I like about Taig:
1) ER16 headstock is not much more expensive than the Taig proprietary tape spindle version. If you only need a few sizes or don't mind making your own collets from inexpensive blanks the Taig proprietary spindle makes collets a very affordable option. The Taig collet set is quite well made if you work with stock of standard dimensions. They are double acting collets so like ER series can close over a wider range than WW, Morse, or other single acting collets. The downside of an ER16 spindle is that you can't use all the nice 3/4-16 thread on chucks and adapters. I used a Sherline M22X1.5mm ER16 three jaw on my Taig with the ER16 headstock and this let me use ER16 collets for much of my work while still allowing the use of an excellent three jaw.
2) T slots all over the place. Easy to stick stuff on where you need it. You need a freaky Frankenlathe configuration? Grab some nuts and machine screws an go nuts!
3) Inexpensive accessories. Example: A toolpost is around $5 with hardware. Radius turning tool is around $20. I milled the tool slot in the radius tool over 1/8 inch so right hand tools could be used. A hole was drilled and tapped at the top of a toolpost so the radius tool could be mounted to the tool post (vertically). Mount up a grinding wheel in the spindle and by using feeler gauges you have a precise radius grinder. Great for making form tools to generate gear cutters, something you do a lot of in higher end antique restoration work! Even complete head stocks are fairly inexpensive, and as it is a belt drive with a separate motor mount, you can swap out head stocks in minutes should that be of interest.
4) Lever acting tailstock. Gives better feel when drilling small holes. Mixed blessings here, see below!
5) Very stiff bed.
6) Carriage moves on rack and pinion. Can be a minus sometimes, but after cranking a 20 TPI leadscrew on a Sherline to get room for your mike or calipers a hundred times you really like being able to just get stuff out of your way.
7) Tailstock slides right off the bed easy as can be. If you use a flex shaft much this alone is a huge benefit.
8) The three jaw chuck is a soft jaw, replacement jaws are CHEAP. Full coverage jaws are CHEAP. If you need dead on, nothing like making a parts nest on the machine. Don't need it often, but it can save the day. Taig has released ER16 mount chucks, so this applied to whatever lathe you go with. Note that the soft jaws on the three jaw chuck are alumnum, so they do not grip with the same strength as the steel jaws on the Sherline chuck.
Things I DON'T like about the Taig:
1) Cheesy graduated no zero resetting dials. Not well engraved, not always easy to read. The cross slide "resettable zero" is a wee spring wire clip you are supposed to slip around in a groove.
2) The threaded tail stock ram with a hard sharp turning center as a permanent feature. Really easy to cut the back of your hand when there's always a hard sharp point sticking out and close to or in the working area. I guess the upside is you can thread a blank to screw on, poke a hole from the head stock, and know that hole in the adapter is aligned with the spindle center line to a pretty good degree.
3) Tail stock ram will wiggle about if you don't introduce some drag. Not a happy thing using very small carbide straight flute drills, they like to shatter if not well mounted.
4) No calibration on the tail stock ram. Drilling to depth requires planning ahead, can't just touch off, reset zero, and poke the hole using a dial.
Improvements you just have to make to a Taig
Get a variable speed motor and rig it up. Once you've had one you just don't want to go back to playing with belts all the time. I used the replacement DC motor and controller from Penn State Industries that cost around $120. Make or buy some decent knobs to replace the cap screws used on the tail stock to lock the ram and the tail stock to the bed. There are some kit like aspects to the Taig lathes, some find that endearing,others think it's irksome