Had a few great games with StMerc and CalgaryFlame.
G is fun (hopefully it's not too painful for merc and flame to watch me let in so many goals :P)
G card is separated from Fwd.... i can't just level up fwd and then switch to G at superstar/legend level....
i notice some lag when i play G. not sure if it is my attribute, input lag or internet lag... very minor... but it's there.
For NHL 12, i found that rebound goal works very well. (when i play D, i assisted many times when i fire a wirst shoot far side and low. this works OK even when some traffic in front of the net)