You will probably have more fun playing bad company, being that the environment is interactive in that game. My friend has both and loves bad company, but it's also because it is easier. I haven't played it but I don't see what the difference is between that and MW2? At least MAG brings something new to the genre, and it's not easy and takes a little getting used to. I never really like the COD games because there wasn't any team work and it was like a bunch of chickens running around with their heads cut off shooting at everything. The first Resistance was fun to me because there was a good amount of teamwork in capture the flag. MAG reminds me of that.
The bottom line with MAG is that your experience will depend solely on the team you are playing with. If you are with a bunch of MW2 players who don't speak or have mics and run around shooting, you will get run through by another faction that is working together. But as soon as you get with a clan that knows what they are doing it is a great gaming experience.