In my revo, I never have. I have an 8Ah pack and never put more than 6Ah back into it. I actually for got to turn on the LVC on my controller for a few months and everything was fine.

In my CRT .5 I run it right down, but I only have 2500 packs and they don't hold voltage as well as they could. (but don't do bad considering the strain I put n them.