I like the build quality of the Acer it feels solid, also the ideal speaker locations for multimedia...
I'm a little leery of the build quality of the Asus, which has been mentioned in some initial reviews, and from watching it happen on the previous 3 Asus models (Signal-gate on the Prime). The speaker placement on the T300 and now the T700 seems to been non ideal for a tablet. They are on the back and right next to each other... I cant figure out why they did this making it essentially mono sound that faces away from the user..... Reports of back-light bleed which has plagued earlier tablets before. The back does scratch easy on this model as I've read a few reports, and it was pointed out in a couple of reviews.
Other then that the Asus has a killer screen, and it comes higher clocked which can help with the higher resolution, and has a newer Tegra 3 chip which helps... And of course we haven't heard of heat issues.