Austy,
I have two of the Beall collet chucks with just one set of collets. The Beall collet chucks use the standard ER 32 collets that you can purchase from many sources. When I was considering the purchase of the collet chucks, I called PSI to find out what size of collets their chucks used. The sales representative who takes the orders could not tell me, so she transferred me to a "technical" rep, and he could not tell me either. My position is that if they don't know their product, I'm not buying from them, no matter the price differential, because somewhere in the future I'm going to want to buy a collet of a size that was not included in the kit and will need to know what style of collet it is. That happened to me once before and I ended up having to have a custom collet made. You get what you pay for in quality and service. Go with the Beall. They are really nice folks to deal with as well.
Danny