I have been shooting both digital stills and HD for many years and P2 since Jan 05. We have a 3 copy rule for images before we will reuse a P2 or CF card (yes, 2 copies should be enough but you know how stuff happens...) We currently carry 5-6 1TB Western Digital Pro drives. They are fast, made up of 2 500gb drives in a ready-to-use raid and have FW 800. They have a fan and you will see people online complaining about that but it's not a problem and the new ones are much better. Best thing is they are cheap ($360.00) and very fast. I love them. When we return we backup everything to cheaper, slow-ass USB drives and then go back out with the 1TB's for the next shoot. Of course you could save the time and keep buying more 1TB drives.
Canon 1Ds MKII - Varicam - HVX200 - HPX500