No doubt Quantum Leap's Ministry of Rock is the best of its kind. However its huge, and consumes a lot of memory while functioning.
A more cheaper and equally effective solution (takes much less memory) would be - using ReFX Slayer2 to generate the electric guitar sound, with Native Instruments Guitar Rig, as an effects device to create the distortion onto it. Amplitube Metal would also help.
As for example, check out my composed rock instrumental 'escape velocity' , on my profile.