Here's a bit more.
Yes therere good.
The milling clamp sets you referred to are really designed for static loads and use on milling machines, the problem being the stepped ends used in conjunction with stepped blocks to achieve the correct height. This arrangement is not considered a safe practice on lathe work.
Always try to use 4 equal clamping points. If you cant get 4 in then use 3, again equally spaced. Using only 2 clamping points get ready to duck.
Trying to tighten just 2 clamps to hold the work piece can lead to damaging or even breaking your face plate.
Last thing, go slow RPM that is fast is not good. If you want to go over 150 rpm you will have to make sure the whole set up is balanced, otherwise the vibration will be a problem.
No this is the last thing face plate work can be dangerous, not just the work piece flying around the workshop, but you have to remember the clamps and bolts that sometimes protrude above the work piece, these not only destroy your tools but also fingers.
Dave