From my understanding the gears will hold up fine so long as your not pushing 17v+ because then you start to need a stronger return spring to get a better ROF and that is what strips the gears.
Servs springs kick ass, very pleased with the results and for the small cost, its brilliant. I got the 4100mAh 11.1v lipo with charger for aubot $85 from a Adelaide Hobby store, its a great combo it seems but I will be intersted to see if my 14.8v lipo or even larger again will help kick some more ass However for a "mild" Stampede it should be reliable and good for all wars and not used for half of one and then melt down. I wanted a reliable, usable gun that I dont have to strip apart every game or always need to be fixing / upgrading parts to compensate.
I fear that pushing past the 16v mark will need more done again.
With my stamp's I have now also done the following:
Removed all internal Safety's - leaving the main switch in tact
Resealed the Plunger with double ORings and Teflon Tape
Sealed Air Holes in the rear of the plunger
Filled rear cap with Hot Glue - in plunger end
Filled Plunger barrel rod with hot glue to strengthen it
Padded Plunger Head
I think tonight I start work on another for my Bro inlaw so I might document everything I do and make a thread on it, i know there is a few already, but i do some things differently then others and with the Lipo mod, it might change some peoples thoughts.