In the case of both Acer and Gateway, the biggest caveat we always feel compelled to make, regardless of specs, is that there aren't any opportunities to customize your configuration.
Right now, there are two pre-built configurations of the U845 on Toshiba's website, which means you won't have the chance to customize things like hard drive size or memory allotment.
They're said to be working on "Samsung-related projects with a mission to customize circuits for adaptation in Samsung products" -- which certainly doesn't sound like typical Intel behavior.