read the gingertiny thread for the changes. They are pretty much the same at this point except the 3/11 changes aren't in the latest aosp kernel.
I would say its faster and better battery life but I suggest you read the logs to see the changes I made. 8/15 is still really good. I doubt you'll see night and day differences between the releases. If you are still confused I can make a summary post with the main changes this evening.
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