Honestly, you nailed it. The minor hardware differences in each phone bring way too many variables into the mix. I've tried almost every JB ROM. Some work well for me, others don't.
With that being said, I tried Bugless on a whim for the hell of it, and so far I've been blown away. It's virtually stock, with a few minor tweaks. The main thing is tethering is unlocked. Visually, this thing is bare stock. Very smooth, 100% stable, and ultra fast.
For me, as far as battery life goes, Bugless absolutely destroys every other ROM I've EVER tried on my Nexus. Over the past four days since flashing I'm averaging about 30 hours (according to Gsam) on a full charge. Normal usage, half wifi/half 4g and about 2 hours of screen time on per day. Before Bugless I was averaging about 16 hours per day on various ROMs, so I don't fully understand what Pete does, but I like it.
Anyway, if you like stock and your goal is battery life I think its worth a flash just to see if it plays nice with your phone.
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