The versions I saw had only a 3 cell battery, so that speaks in favor of the Aspire. Also, since you use a router for the WWAN, is the Expresscard slot that important?
Cheers.
I don't care for a large battery on the machine itself, I have a massive external APC battery pack I carry along with me that I can plug into the laptop.
Expresscard isn't a deal breaker, but I'm happy to have the flexibility, plus I can pop a gigabit ethernet card in it.
I'm also happy at how easy it is to upgrade the machine, you pop one panel off and you have access to the HDD and the memory slot.
The Aspire is a nice machine, but with the S10 around the same price it wins on almost all angles.