Anyone using...Amp Sim 'n gainey Head?

[petemoore]

A 50w Master Lead type amp, and use an amp sim?
 Reason I ask is that I;m about to try at least a couple of the circuits, [waiting a short while till the J201's get here], and the amp tends to be picky about 'what's input'...what better place to ask about than what you folks think as far as a recommendation for my rig...I don't want to build them all !!!
 Plus I like to hear again your good experiences with these circuits..