When I got my notebook a couple years ago, I made a point of getting a 7200 RPM drive (it took some doing back then... at the time there was only the Hitachi 60 GB available and many vendors simply didn't spec the HD speed).
While I don't regret the effort and always felt like it was a factor in the spunkiness of the machine, I ended up with an outboard USB2 drive, anyhow. I actually bought the outboard drive for storage, thinking USB2 wouldn't be adequate but I'm able to use the drive as both an audio drive and -- though it's not recommended to double up -- a stream-source drive for BFD.
That said, the machine works fine for recording audio standalone but I never got into the field recording I thought I would, anyhow... by the time I get my MOTU 828mkII bagged, some mics and stands, cabling, headphones, yadda yadda, it's a big packet of stuff, anyhow. (But I DID get a USB mic for ad hoc field work. Which I STILL haven't done much of.