My input, I run it one of 2 ways normally:
- Stock with deans + barrel/hop rubber upgrade
- "Upper half build" + fet - so piston+head, nozzle, spring guide and spring, bearings, mosfet and barrel+hop. I keep the gears the same until they go bang.
I normally take one built rifle with me, plus a stock version so i know that if the upgraded one shits the bed, I can always go with one I know works (touch wood) and have no more drama's.