If the enclosure isn't using something standard like SATA, be sure to buy as many bays as you think you'll need, because different vendors tend to be incompatible. Also be sure to research if your combination of bay, drive, OS and possibly motherboard will support hotplug, before you attempt hotplugging.
As for drives, I have almost exclusively maxtors here, and haven't had a problem... but maxtors tend to run hotter than other drives, and you *need* cooling for them. A single 80mm or 120mm fan sucking air in across the drive lowers temperatur by about 20C on my drives... increases lifetime.
I dunno if any brand is worse/better than the others, though. IDE disks suck. I won't touch IBM/hitachi for a long time though, their "deathstar" series has left quite an impression. Also, the Quantum (makers of the Fireball drives) had a revision where the name "fireball" fit quite well - one of the controller chips would get so hot it exploded.
If you're shopping an external USB/firewire/external-sata enclosure that needs extra power, BE SURE that the power connector isn't a s-vhs style connector, but one of the "8 laying down", or similar sturdy design. The s-vhs type power connectors break easily.
I'm personally not too fond of USB2 external drives, sometimes (different boxes, different enclosures) there seem to be "hiccups" if running for a longer period of time and/or transferring a lot of data, where the drive disappears for a second and reconnects. I've not lost data because of this, but it's not too encouraging. Sure beats the firewire/filesystem-corruption issue, though. If you need mobility (as in being able to connect to other people's computers), USB2 is the way to go. If you just need something external for your own box, I'd look into external sata or even a gigabit-lan connected SAN solution.
Never do RAID/Stripe, unless you don't care about the data on that drive. It's okay for temp video editing where you need a lot of speed, but never for data storage. I'd even go as far as to advice always using RAID/Mirror for anything important, in addition to regular backups.
RAID/Parity is tempting, but once two drives die simultaneously in a terabyte-sized array with an expensive controller and decent disks, you kinda don't trust that anymore either (fortunately happened to a friend and not me).
XMinus1: I'm pretty sure those iMation drives aren't flash memory but rather micro-harddrives...