Just in case, I found this quite enlightening. Lengthy, but thorough:
Originally Posted by MikeHRC
The point that I was making was that you don't use EPAs to set the swash flat at each end of travel as you would with a FB heli
Yeah, but as mentioned a few times before, you shouldn't
actually do so with a FB helicopter either. It will influence servo resolution and performance.
I should clarify that you can
use some EPA, but it should really only ever be used for fine-tuning what can't be gotten more perfect through mechanical adjustments. Often times people use it to 'fix' really huge mechanical issues, because they are lazy (or oblivious to the side-effects this can cause).