This is really a question of where you are at musically...I traded my Mark IV head for a Lonestar Special...reasons...compact and easy to carry around for gigs and practice...unbelievable clean channel, that really gets that true slightly broken up sound...a lead channel that sings...believe it, I get more sounds out of it than the Mark IV. It really depends on what you want to play...if you need to sound like John Petrucci, then stick with the Mark IV...however, if you need an amp that is versatile for just about any gigging situation, minus Metal, than go with a Lonestar. I can't tell you how happy I am with it. Check out some of my tones at www.myspace.com/urbanburnreggae. The track titled Rightousness is particulary worthwhile, as there are some great examples of the tones from this amp. Also, you mentioned Led Zeppelin...for a warm-up before shows, the sound man puts on When the Levee Breaks for me, and I jam to it...I NAIL that sound