I just bought the Sony HMD A400/L and like it pretty much. There's an $80 rebate on them now, which should bring the price close to $420..
The only "problem" I have with it is the 75Hz maximum refresh at 12X10X32. I haven't noticed any flicker or eyestrain as yet, but I guess I've been programmed to think it's got to be 85 or above or your eyeballs will explode.