In my current game I have a gestalt soulknife/urban ranger and a gestalt fighter/psychic warrior. My players, especially the ones who have played the longest, at least find them interesting enough to consider. I thought they didn't work very well in 3.0, but love them in 3.5. I'd run an all psionics game if my players ever wanted to. I think most of the hate for psionics is rooted in older editions, but I think my group understand the difference.