I got a Rosewill dock a couple months ago in one of these bundles and I've been having problems with it. I'll be copying files, burning a DVD, etc. and suddenly the operation will stop because the computer loses the connection to the drive in the dock. Sometimes I can get the drive to remount by unplugging the USB connection and plugging it back in, other times I have to reboot the entire system. (Further oddity: sometimes when I do the unplug/plug thing, I get the standard error message about removing a mounted drive, which makes me think the computer believed there was something out there. Other times I don't get the message at all as if the drive had been dismounted.) I have two NexStar docks that don't have this behavior and I have 9 or 10 bare drives that only exhibit the behavior when in the Rosewill dock. I've moved it to a different computer with the same results.
This could very well be just a dock with a loose connector or something, so don't take it as an indictment of Rosewill. I'm wondering if anyone else has seen similar issues.