Dremel isn't what it use to be, since the company was sold. It appears to be more interested in selling new units. They are changing the designs more frequently then they have in the past.
Case in point the first version of the lithium battery one is different, then current one.
I have a number of them, from a 200 series to the 400 series that has the small planer attachment and jig saw attachment. They both work great only thing the planer does remove more material than it looks. Cut once and measure twice.
I like the lithium battery one as it can be used on a ladder and they last charged for a long time.
I have one that I use for cutting dust generating stuff, tile, grout, stone and the like, that way I'm only destroying one unit at a time.
As to the Dremel accessories, The plunge router works better for softer woods and materials. I used it on some oak, it worked but was slow due to numerous thin cuts/more passes.
I had the old version of the router attachment years ago and made doll house size trim and wood parts small work and a slow feed.
The router table is now a plastic light weight styrene type, and needs to be screwed down to use. It is the same as the other items in the router type, light, soft materials work better.
There are people that use the drill presses stands and router tables as milling machines for thin brass copper and aluminum. Again the speed, many cuts, and a light touch.
You have to remember that the Dremel is a hobbyist level tool and made as such. Podiatrist's use them and some other doctors for removing casts, along with the nail salons and pet groomers.
I have a number of them as I tend to use more than one bit at the same time, saves a lot of messing changing back and forth. All mine Have the keyless type chucks installed.
I have two of the HF flex shafts Foredom knock off's one has drill thousands of holes in assorted material and works fine, They were the original versions. the other has the wood chisel head attachment and work ok for that.
You can buy flex shaft attachments and make up a coupling for an electric motor, or chuck it in a drill press for slower speed work. I made a coupler and had it on an old dryer motor.
Both my parents are master wood carvers and have the Foredoms they like them for certain things.
The rotozip is now owned by the same company as Dremel. they work great and the accessories can do some nice set ups/jobs.
I have a Porta cable version Older model they no long supply parts or accessories for it. I wouldn't buy that brand again, as the guy at the tool saw sharpening shop told me to pith it and buy the new version. Nothing wrong with the old version other than I didn't have the accessory table attachment.
Pencil air tools, as long as the air is dry and you keep the lubed are fine if you can control the speed or have the bits that can take the speed with out burning up. They are better used with stone mounted points than bits.
Proxxon electric tool like the Dremel, are more robustly made and are also a good choice.
It depends on the use of the tool, and the rated duty cycle of the tool, and what you care to spend.
;D