Vaio Pro or Aspire S7?

So, I've wanted an ultrabook for a long, long time, but I've held out in a hope that my desktop would suffice. But last week I got into my brain I really want one. It's essential I have 8GB of RAM, but a 128 SSD is fine. So the question comes down to the Acer Aspire S7 or the Sony Vaio Pro?

The Vaio pro is slightly lighter, which is nice, and a slightly higher battery life than the S7. The downsides of the Vaio Pro appear to be sharp corners, and the Verge didn't like how it flexed (though other reviews seem to ignore that). The new S7 is generally all-around good.

I'd be interested to see what anyone thinks, especially if they have them. Relevant information would be the trackpad quality as well, but from reviews, they seem to be comparably "okay," for Windows trackpads.

I was also interested in the Samsung Ativ Book 9+, but I kind of feel like the price for the 8GB model would be way too much. Though its battery life does seem slightly better than both the other options:

What do you think?