I'd sell the TSL and look elsewhere. 5150III,6505(+),mesa mark series...
because that TSL is just going to become a money pit, and you'll never really achieve what you want out of that amp.
that amp sounds just fine to my ears(like stated above, jcm 800 tone is very noticeable). sounds more like you're not really hitting your guitar strings hard, resulting in a more clean sound (if that makes sense). you can always change preamp tubes just to be sure, but i don't think it will be a...
tube screamer seems to be the norm for metal players.
I use a Boss SD-1 i must say it does the job well(and is quite cheap to purchase).
Maybe you could take your amp into a music store, and ask them to test out some OD-pedals, I'm sure this won't be a problem.
but surely those times are changing? people don't take this approach anymore and demand a quality instrument for the hefty price (i know i do). Gibson should realize this, because if they don't, i predict sales will be slow for a little while longer
i'm really wondering where Gibson gets their ideas. i mean,who decided for all the changes in the 2015 lineup? and why? did the guitar playing community ask for those changes?
i bet if Gibson would actually listen to what guitar players want, sales would be way better than they are now. the...
i think Floyd will win this one. dude has a reputation(undefeated) to defend. i doubt he'll risk his reputation over a wad of cash, guy has to much ego for that.
and McGregor seems like an uncontrolled type of guy, probably will survive a few rounds, then make a mistake and get KO'd by Floyd...
as charvelfan said: metallica did this while recording the master of puppets album.(they used a jcm800 though). if you find plugging the triaxis into the jcm900 too much of a hassle, you could try and find a used marshall poweramp (20/20, 50/50) and put the triaxis and poweramp in a rack