1) The Crosman Quest is the same gun as the Phantom - except that it has a wood stock, and is usually a little cheaper.
2) I suspect you'd find the QB36-2 to be less accurate and less powerful. "BB" tested the TF99 (QB36-2) on
http://www.pyramydair.com/blog/2006/12/tech-force-99.html, and found it to be a mediocre performer. Plus, the Shanghai factory that makes them is known to have spotty QC.
3) Crosman has decent parts support for their current products, both in coverage and in price. Not so with Shanghai.
4) If by some chance the sear and beartrap mechanism would fail while you're loading the gun, the Crosman won't chop your finger off like a sliding-breach type gun can.
5) The Crosman is lighter.
6) On the down side, the rear sight on the Crosman is a POS. It works, but it's flimsy.