Over the years I've become very sensitive to keys, there really is a big difference. Here are a few of my favorites;

Playing Blues;
G (my favorite, kinda dark sounding), E , and Bb. Eb also sounds nice but can be a pain in the butt unless you tune down. I Hate Blues In A, to damn bright, same w/D & C.

Minor;
E and A minor sound really nice, as does D, C, & G.
The only really minor key that bothers me is B, just never sounds good to me.

Major.
These I'm real picky with. I enjoy G.....E and D can be okay depending on the song, but generally I much more prefer the flat keys when dealing w/ major (Bb, Ab, Eb).
Definitely not a big fan of A & C, too bright, too much clarity.