R6: 3 (Xbox) was the first R6 game to go from super tactical, no real main character, "realistic" (for its time) to full out run and gun FPS. It was a great multiplayer experience for console users, but stale otherwise. R6: Vegas was not a very good game. I wouldn't recommend either in that series.
I think the best console shooters so far are Orange Box, CoD series (excluding 3 and 5), and BC2. If you're into multiplayer, CoD:MW2 and BC2 are going to the your best bets for finding games, next in line would be Orange Box for TF2 (which is another amazing game, even the update free console edition).