As a previous note owner (sold it due to personal preference regarding size), the S3 suits me better - size wise, I'd put it in the middle between the S2 and Note, as the screen size indicates. It fits comfortably in my jeans front pocket, is useable with one hand, and provides the extra screen size I was looking for. Touchwiz UX is MUCH less intrusive - this is the first Galaxy Android device I am considering using with stock OS. Performance is really snappy, even compared to Note with ICS, but battery life is less stellar than the reviews led me to believe it would be. I loose about 6% overnight with it on flight mode. With the S2 and CM9, it was less than 1%.
That said, I am a light user, and am confortable that it will take me through 2 days with (again, for me), heavy usage. First charge yielded just over 48 hours, with 3h50 minutes screen on, 40 minutes of voice calls, about 20 minutes of YouTube streaming in HD, WiFi on and syncing mail and calendar full the time, and 14 hours on flight mode while I slept. Fully charges in about 3 hours.
Downsides: white only for the next couple of months, and awful Vodacom branding in bootup and shutdown screens. Also available from Samsung HMD stores, but about R250 more than at Vodacom on cash purchase.
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