[Nexus 4 General] Ryou_Concord:
Here's my setup:

Cm 10.1.2-mako

Kernel: mako-jb-kernel-016m

I'm currently running an older kernel of Faux123's, which was the one he made for 4.2.2, since his newest one was built for 4.2.3 and all my phone would do is boot up into a black screen. It was a little tricky to find, at first, but I eventually found where Faux put his builds for 4.2.2.http://faux.androidro.ms/mako/jb42/ So if you're having that problem like I was--and you're enjoying that wonderful transitional period between 4.2.2 and 4.2.3--look no further.

As far as undervolting goes, I've only just started experimenting with it, and while I haven't noticed improved battery life, I have noticed a huge decrease in heat coming from my phone. I was connected to a charger for a couple hours in a car ride with my WiFi tethering on (so I could browse the web on my N7) and I noticed that my N4 wasn't getting nearly as hot as it used to. I had undervolted it by -125mV all across the board when I experienced this, but the kernel I was using wouldn't operate at these voltages in a very stable way. It seemed that once the battery dropped below 30%, I couldn't undervolt without the phone locking up.

However, that was on Franco's kernel. I recently switched to the Faux123's kernel and flashed it a few hours ago. I had the same problem where I couldn't seem to get any of the voltages below 800mV at 162mHz (It initially threw me off when I learned Faux123's FauxClock app displays freqencies in kHz instead of mHz), so I rebooted it. And then it magically started undervolting it below 800mV. Maybe it was a setting I turned on or off, but here are my voltages:

162000 kHz: 675000 uVolts

216000 kHz: 675000 uVolts

270000 kHz: 700000 uVolts

324000 kHz: 700000 uVolts

378000 kHz: 725000 uVolts

384000 kHz: 725000 uvolts

432000 kHz: 750000 uVolts

486000 kHz: 750000 uVolts

540000 kHz: 775000 uVolts

594000 kHz: 775000 uVolts

648000 kHz: 800000 uVolts

756000 kHz: 850000 uVolts

810000 kHz: 850000 uVolts

864000 kHz: 875000 uVolts

918000 kHz: 875000 uVolts

972000 kHz: 900000 uVolts

1026000 kHz: 900000 uVolts

1080000 kHz: 950000 uVolts

1134000 kHz: 950000 uVolts

1188000 kHz: 975000 uVolts

1242000 kHz: 975000 uVolts

1296000 kHz: 1000000 uVolts

1350000 kHz: 1000000 uVolts

1404000 kHz: 1012500 uVolts

1458000 kHz: 1012500 uVolts

1512000 kHz: 1025000 uVolts

So far, everything's stable, if not a teeny bit herky-jerky when I first turn the screen on. I'll report back in about three days or so.

EDIT: 14 AUGUST 2013

Well, yeah. Everything acts a little more herky-jerky than I'd like to, but it's nothing I can't handle. I definitely feel like it's running cooler, since it doesn't almost burn my hand when I'm performing most tasks. It rebooted randomly, maybe once, but everything seems solid.

Using Faux123 Kernel app, I can actually see what all four cores are doing--or at least have a better idea of what they're doing. With mpdecision off, Intelliplug becomes active, and I can switch on Eco Mode and Snake Charmer. On Eco Mode, I'm only using 2 cores, so it's usually quite slow if it's below 1.134ghz.

With Snake Charmer on, keeping it clocked at about 702mhz, basic tasks function pretty decently. Every now and again, the voltage values don't stick inside the app, but if I reboot my phone, that seems to fix that problem.