I use the palmer PGA-04 for recording real live tube amps, it a power soak and a direct line out with filters so that you can inject a line level signal right into the sound card line in.
Two things that make The PGA-04 awesome.
No microphones to deal with, the amp is totally silent.
The filters inside the Palmer are first class, it sounds like the real amp, not a line out on an amp and you can dial in several of the Palmers filters to suit the amp and your taste.
I use Guitar rig more for overdriven sounds. It has plenty of clean sounds but so far they do not compare to my real tube amps. GR is just so easy and fast to record with once you set up all your custom sounds.
Well maybe if I fooled around with GR some more on clean sounds, I could come up with something, but I have a large stack of real tube amps here and I have to fire them up once in a while to justify owning them. :rolleyes: