Between the 7.1 and the Mtroniks, I'd choose the 7.1 It seems like a very reliable ESC.
Mtroniks i've used their RZ before, tons of punch, however, they tend to make my batteries run very hot. Runtime is slightly decreased due to it, but mine runs more than 5 mins, sufficient for 5 min races.
The 7.1 should perform adequately in stock (we run 23T stockers here), i'm sure it can take mods too, my friend runs a Trinity P94 9x2 on his
BTW, why are you posting getting a TC3 or T1 here, odd place, no?
I'd take the TC3, assuming the parts support is better than the T1. Else, id' take the T1. The Xray T1 is really a piece of r/c art, but setting it up can be a pain in the ass, especially since you mentioned you do not have esc yet i'd hazard a guess you do not have acquired the setup tools for it.
Dragon: Is your Quantum Competition back from repairs? I did not see you at the tamiya race
Your TBEVO and QComp/3PJS combo should be kicking some major ass, no?