I know you did not ask Donny but I have the Surface Pro. I adore it for a multitude of reasons but battery life is not one of them! Honestly .... four hours if I am lucky. I believe the Surface 2 is better but I can't imagine it would be on a par with an ipad.

I did have an ipad 2 and an ipad 3 ... the 3 was the one that introduced the retina display and it still gave a good 10 hours. Also that retina display is so glorious. If you don't want to splurge on a new one ( the ipad air) I would recommend the third generation just so that you get that wonderful retina display. You won't be disappointed on the little extra you would have to pay over an ipad 2.