My personal opinion, and this is all about opinion, is I'd rather go eyefinity. The main reason is that I would not like to wear glasses every time I wish to game in 3D. Eyefinity doesn't have those constraints.
I have a great pair of Dolby 7.1 headsets that I rarely use, because having to wear equipment to play a game is annoying. Sure, I occasionally put them on, but it's just not enjoyable for long periods of time.