Laptop hard drive speeds. Are they a problem?

I'm looking at buying a new Toshiba laptop (because I can, kind of)and the seriously attractive specs'in regards to DAW work I need are great- except I'm baulking at a HD access speed of only 5400rpm. Wouldn't this be an Achille's Heel negating the P4, large RAM, etc? I'm wondering if all the fast componentry is pointless, if the HD can't read or write fast enough. I'm used to expecting at least 7200 rpm with a desktop.
Or have I got the wrong concept?

Cheers, Bag.