I always liked Paul Gilbert & his music, found him a brilliant player, but a rather generic / clone sounding one. I could never distinguish his playing from other guitarists, where Sheehan you know it's him after a few bars. Billy has really built a signiture sound & style like it or not.
The new album is pretty darn good, really play as a unit, very tasteful, only small amounts of wankery, which is what you want & need.