I have owned a number of Pass Amps and pre-amps, as well as several First Watt Amps.
Right now I have a xa30.8, and x20 pre and x10 phono.
Every Pass amp and pre amp I've owned has sounded a bit different, but they've all sounded excellent.
The people at Pass are great to deal with, as is Mark from Reno Hi-Fi ( where I've purchased all my Pass equipment).
I suppose there is better equipment, but I would say that if you are not satisfied with the sound of Pass then you will likely not be satisfied with anything.
Of course this is just one man's opinion, but I think it's a valid one.