This has worked well for me... I was using the 4.5.0.124 or whatever that was the East Asian version and it wasn't playing nice with my battery. Having wi-fi enabled was running down the battery in just over 24 hours (and I needed it for UMA at home where the signal is weak.)
This version isn't killing my battery as badly - back to how the batter was working with 4.2.2.193, more or less.
Thanks T-mobile... now I just can't wait for the touch pro 2 release