Drobo and a big ole drive

took the plunge and bought a Drobo, with the intent of making some brainless backups. I’m concerned about the RAID5 onlyness, having no experience with a striped drive like that. everything I’ve had in the past is just plain vanilla mirrored backups.
it was long past time to switch from the myriad 20g drives that I’ve been scattering my data across.
i’ll update with experiences in future!