Yeah 6s is going to equal bbq no matter what you try to do. But the 1st gen EVX2 without lipo cutoff has been proven to handle 5s (with a fan added to the esc) many times with the hack I mentioned in my last post. It should be noted that I haven't seen anyone run 5s on the newer EVX2 with lipo cutoff though. So I'd do some more research before trying it with the newer EVX2 that has lipo cutoff unless you're ok with possibly bbq'ing an esc and have that fire extinguisher handy.

And if you want to try the 5s trick here's how you figure out which esc input powers the bec. Plug in a pair of 2s or whatever you have that totals 16.8v or less. Power on the esc and unplug one of the batteries noting how long the led on the esc stays lit. Plug it back in, power up the esc and unplug the other battery again noting how long the led stays lit. The led will go out quicker when you unplug the input that powers the bec, mark that input lead somehow (tape, zip tie or whatever) and only use 2s on that input. If you have a fan for the esc and want to try 3s on the other input do so at your own risk.