mdrone,
I own an LS100 and an LTA MZ2.
The LS100 was my daily driver for years and is a great preamp, plus Dan Wright is a joy to work with. It has no obvious flaws, and does just about everything right.
But in my system (Atma-Sphere M60s/Zu Druid Vs), the MZ2 was just slightly better, with the same great tonal qualities plus better inner detail. I lucked into an Atma-Sphere MP-3 preamp which, unsurprisingly, is the keeper, but the MZ2 stays as the spare and I'll be selling the LS100.
If you're looking at the MicroZOTL, I can only imagine it's a big step up from the MZ2. Hope you get a chance to hear both. You can't go wrong with either one.
David