Revalver MkIII.V is good, but I prefer the sound of the LePou plugins, which are free...
http://lepouplugins.blogspot.com
Couple these with cabinet and mic IRs from the likes of Redwirez
http://www.redwirez.com and you will have a great sounding and versatile virtual setup. No effects, but great for straight amp sounds. Especially good for those on a budget.
Cheers.................................... wahwah