I'm all on SVX, but there are some others. I've given up on outboard modeling after having four or five of them reveal unremediated bugs or else unceremoniously croak just sitting there.
Guitar Rig has surprisingly got some great bass sounds. (I am primarily a guitar player though).
But it has really impressed a band I recorded with recently - They thought they bass would let the recording down .. but It actually ended up sounding amazing
I've heard good things about Ampeg and Trillian though.