I reckon these J900 size collets are pretty rare here in the UK.
Its a bit more likely to chatter but not too much.
I also have ER25 collets but these have are a pain to release. i have to sort of undo them twice.
This chuck releases the collet at once and its just like using the key on ordinary Jacobs chucks.
I work quite a lot of biggish plastic material and one advantage of this chuck is that you can work a 300mm stock bar, without cutting off a bit to work on, to reduce the stick-out. Saves a lot of odd-end left-overs.
Normally these chucks come on a non-threaded mount of various types.
This one fits on an ordinary back-plate which you must machine to fit.