High cell count, when to add a receiver pack?

[BrianG]

Most controllers I've seen say no more than 12 cells. Otherwise the linear regulator heats up too much and in turn causes the ESC to overheat quicker. 8 to 10 cells should be fine, but some people still use a BEC or receiver pack anyway to fully take that load off the ESC. Receiver packs are relatively heavy compared to a small UBEC, so you might want to check into that...