I'm on an L930 (UK variant) and made the jump from slow ring to fast with this build.
The reason I wanted to try the latest build was that I got a Sphero BB-8 for Father's day and the app didn't work on the old build (it put up a "please enter your age" page, but wouldn't actually take any input. On the plus side, with the new build, this worked (hurrrah - not a sad Dad on fathers day).
Sadly, I'm having massive battery issues, though.
- On standby, I've seen that I'm using somewhere between 10 and 20% an hour. One culprit seemed to be MS health (I thought they'd fixed that a few builds back!).
- Actually using the phone seems to drain ridiculously fast - a 7 minute play with BB-8 seemed to use about 25% of battery, as did a 5 minute game of King of Thieves. Admittedly, KoT always used a lot of battery, but it feels like this build the usage is higher (but maybe I'm just super sensitive given the very poor standby performance).
I only updated yesterday, so am still in the 48 hour window that people say you need for builds to settle down, but its all a bit scary at the moment!