Just downloaded the beta version of TSE's X50 amp sim today (his take on a 5150/6505+/etc) and whilst messing around with it found myself writing the first heavy piece I've been reasonably happy with in absolutely ages. Ironically, I'm not totally happy with the tone, but I just cannot take any more tweaking at the moment, and it could be worse, so figured I'd upload a demo anyway!
All guitars are TSE X50 (boosted with TSE 808) + Recabinet impulses, apart from the cleans at the end which are straight Pod XT Live. Bass is disgusting, I'm afraid - my actual bass is in Bristol, so this is nasty pitch-shifted guitar, but I guess it serves a purpose if nothing else... Aaaand, the one thing I'm reasonably happy with about the mix is a new drum sound from S2.0! Oh, and synths are Philharmonik CE.
Input would be hugely appreciated on both the mix and the composition - I'm pretty happy with the latter, not so much the former, but any thoughts would be more than welcome.
EDIT: Here's the second update, with better mix and a new section...