netspanner: I totally disagree, even though I have no idea what a wakeboad is. I have used it since I got my phone in May last year. When I bought my wife the same S2 she was down to 30-50s% each night while I was still in the 60-70s%. When I put it on her phone it mirrored my battery levels. Right now, 9pm, I am at 66% and she is at 84, with our phones charged up overnight. we have stock phones and use a number of apps
You can't really compare devices like that because there are so many other factors that can be involved with battery life including usage (length and type), signal strength and applications installed.
You really shouldn't need to cripple your phone using Juice Defender with a GSII