vegas was great but it had just as many annoyances as mwf2 from what i remember. certain places you use the wall cover to shoot through objects so that you could kill people but they couldn't even see you. the shotguns had godly range and the spawn system was awful. i remember spending many nights playing vault with a few friends after i bought my 360 and a copy of vegas though... real good times.
That's why I still prefer my CoD2 over both of the CoD:MW's to this day. Modern Warfare 2 really is a free for all. Run, gun, die, respawn, repeat. CoD2, much smaller 4 v 4 games, a lot more strategy, and still hella fun to this day.
Bordertown was my favorite map. I'd play with the same people every night, and we take the back alley spawn and pin the other team in the church - ultimate spawn rape. After that though, we'd take the spawn inside of the church and beat their asses in the alleys, just so they'd shut the fuck up.
that was another favorite along with killhouse. i thing vault, bordertown, and killhouse were my top 3 maps in that game.
i remember playing terrorist hunt my first time online with it and played with these 2 guys and we would play together like every night for weeks. they are both still friends on psn...good stuff