Spec wise there pretty similar
Both have 4.3" displays
Both shoot 1080p and have ffc
Both are 1.2ghz Dual-core
Both have 1gb ram
Both have hdmi out
Only obvious difference is evo has 3d cam and 3d display but galaxy 2 diaplay is wayyy batter in terms of quality not res.
Build quality of htc evo 3d will be better, im sure, but the GSII is like half the thickness and very light, so thats sort of a draw. Release is around the same time and im sure price wont differ that much.
Which one should a person choose considering the whole 3d thing is sort of a gimmick and im going to barely make use of it???