E-Maxx diff advice needed.

[Patrick]

I would choose option #1 as well.
UE cases are $70 a set aren't they? So $140 for 2, that's the same price as the FLM hybrids, but the hybrids have aluminum bulks built in.
Stock diffs gears may last a while with al cases, but with your setup they'll always be a weak spot, so 1/8th diffs may be less hassle in the long run.
I suppose if you don't want to spend $270 in one go (again) you could use the UE cases with stock diffs for now and get the HB diffs later on, but I would prefer the hybrids if it was me.