I got both THR10 and THR10C. THR10 came first and thoroughly impressed me. Convincing concept, first modelling-amp I could actually take serious. Good onboard effects, great additional functionality once you hook it up with the computer. I used to be one of these tube-snobs (Orange OR120 ('76), Engl Gigmaster,..), but to deny the useability of this product would be plain ignorance. It is actually a bliss and a very inspiring addition to my rig. Hence, it was an easy decision to get the 10C aswell. Anyway, to answer your question: the THR10 breaks up later. THR10C has more of a tubescreamer-feel to it, especially with high output PUs. I recommend to check out some videos though, both are quite different in character.