I'm building (slowly it seems...work) an flm Emaxx running a 125b, 8XL on 6S a123s. I chose to go with the flm hybrids with 1/8th diffs (the ones sold to go in UE diffs) cause I didn't want trouble. I'm using UE TI centers, but went with RCM output shafts so I could run 3.3 cvds with the GorillaMax suspension I bought.

I've built several sets of trx based diffs using flm diff cups (they're cheaper and I like the guarantee) with the modded ring gear and 3mm screws. I put them in the cheapest alum cases I can find - I've used gpm, integy and GA (ebay). The alum case is a must to keep them from twisting which lets ring pull away from pinion and causes it to eventually strip. This is an intermediate solution - they've held on any nitro I've put them with, up to a 28 with no probs. BL makes so much more torque, I'm not sure how long these will last, may depend on gearing to some extent.

I'm getting ready to try a set of these in my Emaxx (older one) - the stockers are gone. I run a pr of brushed S600 motors in this one on 14cells. Its enough that I can twist the plastic axle shafts easily. I 'm hoping these diffs will be strong enough.