There is a lot of personal preference in the answer to that. You need to put your hands on both to see how they feel and look, then decide which has the features you require.
I know this isnt one of your choices...but...I was in your position a few months ago and I went with the asus eee pad transformer (I handled them all). IMO the best of all of them. Has 2 usb's, hdmi out(accepts external hdd), 10.1" screen dual core tegra 2 processor , gig of ram, all the bells and whistles a growing boy or girl would need...lol. Did I mention you could also get a fully functional keyboard dock that also acts like a extended battery... Happy hunting, but you just cannot go wrong with the transformer...good luck