I've used their 2.5" enclosures before. The only reason I'm not still using them is the paint on the ends started to wear off, and I wanted a second FireWire port (the bytecc only had one FW and one USB2 connection). I ended up getting several MacAlly enclosures and I'm very happy with those.
I have one of bytecc's other USB2 enlosures holding a 200GB Seagate IDE drive at home. It works when I need it to (I only turn it on when I need it) and is only as loud as the hard drive inside it. With no fans, it's quiet and doesn't heat up more than you would expect. The aluminum enclosure wicks the heat away from the drive, keeping it well within operational parameters.