I can vouch for the Revolution HD ROM
About a month ago I switched from the pre-installed T-Mobile ROM to Revolution HD 51.0 on my Samsung Galaxy S3 (GT-I9300) and I have no regrets. Compared to the T-Mobile Rom, it is extremely fast and with very light battery consumption. In addition, I have not yet encountered any bugs.
The Revolution HD ROM is so fast that I have now begun using the search feature in the dialer - before, it was just as slow to scroll with the alphabet and finding the contact as it was using the search function.
The battery consumption is incredible! With light usage, my battery goes down less than 0.8%/hour. Even with high usage (>1.5 hour talk, ~1 hour WiFi/mobile data internet, >3 hour Bluetooth hook-up to my car, a handful of written emails and >30m sudoku per 24 hours) I have not been using over 1.4%/hour. I have gone from recharging every two days to every three-four days! My record was 97 hours without a charge and still 18% juice left in the box.
I use GPS navigation once in a while in my car and that consumes a lot of battery, but then the device is always connected to power (I haven't gotten around to try GPS navigation without charging just to check the consumption on Revolution HD).
I am not a techie, so I have disabled background services very conservatively (I killed most social app stuff, but I let services with cryptic names be) and I am using the Lightning browser which is fast and very light. In the beginning, I had a bit of trouble with battery performance until I read that the Power Saving feature must always be on. With the T-mobile ROM, the screen was a battery hog even when set on auto, so I set it manually - on the Revolution HD ROM, the auto brightness works well and conserves battery. It should also be said that I live in an area with good signal reception and coverage is good in most places I go (in areas with low reception, the device will automatically increase the juice for the radio unit).
I am very excited about the Revolution HD ROM, but I cannot tell you how it performs if you do a lot of social networking stuff (I primarily use the phone for work).