With the rx8 gen2, I run hv servos without issue, no bec, no glitch buster, and with my spectrum rx.
What's in my most recent eb48 is a protek 150t, which is .1/345@6 and .08/[email protected]
If you want even higher/faster, their new 170s team edition is silly specs, that's one I'd consider running on just 6v.