First off, your not going to find much information here since I think only 2-3 members here have turbo'd their 2.2s. Check out jbody.org or it might be .com...
The have a LOT of info on the 2.2 engines, and they've done everything to them..
To answer your question on the 2.2 vs 2.0 question? Well its simple, GM designed the 2.0 with forced induction in mind, so it has forged parts that can withstand the stresses of extra air pressure. As for running 15psi in a 2.2, I think all you'd need would be pistons and rods, but don't quote me on that.