I got myself a cable 'usb to ide/sata cable' for less than a tenner. No caddy needed.
It means I can plug all other stuff into a usb port, 2.5 HDD's, 3.5 HDD's, ide, sata, CD/DVD RW etc. to use as and when I wish.
Wouldn't be without it now, it's solved my prob of pernickety drives.