I'd shoot for whatever storage medium has the fastest access time... if that's the USB stick drive, go for that, if it's the hard drive (although I doubt it... access and seek times in particular can make those slower than sticks) go for that...

Or just make it so ANY attached memory can be accessed by the MFD

BTW, G70 has 50MB flash RAM, with about 25-30MB free for the user... and a PCMCIA card slot that is exactly as fast as the internal (where I have 4GB attached )