Personally i would almost always chose a chuck over a er collet set up if accuracy's allow. open and closing a ER collet is slow going. Its fiddly having to align a hook spanner and lock the lathe spindle by changing to a slow enough gear to be able to undo it. Add in it taking multiple turns to actually get the work lose. A Er due to slop in the nuts retainer normally always needs at least a full turn to go from tight to popping lose. Not a major issue on a mill spindle but a pain in the ass with a lathe bed in the way. Then repeat this to tighten.
Compare this to a chuck key that sits and stays in a hole and only needs a half turn with no locking of the spindle and its far more productive.
A "Proper" work holding collet set ups always done very differently to how a ER is. Cam locking or draw bar style locking that's far faster, far simpler and easier to do.
So i guess that makes me a retard Zagnut. All i do know is that i can use a good chuck and make you look so slow over a full work day using a ER collet set-up that your probably getting what ever the equivalent of a p45 is over there come the days end!!
With high quality products and considerate service, we will work together with you to enhance your business and improve the efficiency. Please don't hesitate to contact us to get more details of Collet Chuck.