Home Forums Peripherals & Multimedia Peripherals 5400 vs 7200 on Backup

I can get a 320 GB drive on sale today at a pretty good price. It will match the size of the 320 in my iMac and will be used as a clone backup drive. However, it is only 5400 rpm. The question is: Do I care if it's only for backup and limited applications use?

My backup M.O. is to use Super Duper, allowing it to make the clone and shutdown afterward, so it's not like I'm in a hurry for that part.

However, I use the clone as a boot drive when running applications like Disk Utilities, Disk Warrior or TechTool Pro. There will never be anything as intensive as games et cetera. Are the utilities' performance likely to be affected enough that I'll be wishing I had 7200 rpm?

EDIT: Updating the information....I was just checking this drive on-line and see that it's USB 2.0 (although it says upgradable to FireWire 800...without saying what that means). I currently use an 80GB drive I recovered from a previous iMac and it's on Firewire.