I got this Sept last year and have enjoyed it many times since.
The picture quality is more than acceptable - not like an HD TV, more like cinema quality if that makes sense.
It's my first projector and I remember my first thoughts of the picture quality being very impressive.
I have it on a screen at about 82" and use it for movies and Grand Turismo (Playstaion3). No problems with the quality at all.
I wouldn't be happy using it for TV viewing daily (I have an HD TV for that) but for occational use it is great.
The fan yes I can hear but it is not annoying at all and your mind blanks it out to be honest.
Not used the 3D or bought the adaptor so cannot comment.
A friend has a £800 Optoma projector (HD80 I think). The quality of that is much better, very similar to an HD TV. But for £400 ish the HD600 is I think a bargain.
If you want HD quality go elsewhere and spend more money (2x the amount from what I've experienced), otherwise I find it great for occational movie use and more than acceptable for GT5!