How Fast is USB3 on the MacBook Pro 15"?
Plenty fast for most everything, and way better than Firewire 800 (which maxed out at 40-80 MB/sec vs ~270 MB/sec for USB3).
Not as fast as an internal SSD, but so what? USB3 will improve my life in the field when making backups of any kind, for overflow storage, etc. Very practical for storage expansion on a MacBook Pro— at home or for travel.