5v or 6v on ubec?

What kind of amperage can most radio gear take though? I got the Castle BEC and could crank it to 10a if I really wanted to, but don't think my servos or rx would like that. I have a friend who made a couple little linear regulators that put out 5v and 3a, he wired them up in parallel to put out the same 5v but 6a......and made his crawler's Hitec 645MG VERY hot! So, maybe 5a max? I haven't decided if this will be in my crawler or in a different car, but it'll most likely be powering a TowerPro 995MG.

Sorry if this is too off topic......