I bought WAY too many guns in 2009. Still haven't paid them all off either (bad, I know). Most satisfying, I guess would be my first AR (S&W M&P15X). All of mine are pretty satisfying, probably because I'm the type who spends hours agonizing over most of my purchases, so I usually end up with what I want.
Hopefully in 2010, I finish paying off my 2009 purchases, and focus on ammo and reloading stuff.