I have one of these
. It may be big, comparatively expensive, and the fan does make some audible noise, but it does keep the drive much cooler than normal enclosures. It doesn't look or feel too cheap either. The fan could maybe be modified to run slower or maybe even temperature-controlled if it's too loud for you. Also this enclosure doesn't do much to stop vibration noise, but what enclosures do?
They are good enclosures but they have one critical flaw for me. It uses a funky 4 pin power connector. This may not be an issue for you but let me explain why it is for me.
Looking at my shelf I see several Seagate external hard drives of varying capacity. They want 12v@2a on a 2 pin connector.
Next to them I see several WD external hard drives of varying capacity. They too want 12v@2a on a 2 pin connector.
Looking at my desk, I see a USB cable and a 12v power plug. I can take anything I want out of the shelf and plug it into those two cables.
This might not be an issue if you either a) buy exclusively the antec enclosure or b) don't have many external drives or c) don't mind storing a wall wart along with each and every hard drive in your shelves. But for me, the one remaining external drive I have with a funky power plug is in the pile with zip and jaz drives to have the contents transferred to a usable format should I get around to it before the bits fall off the media.
That said, I am moving away from external enclosures for rotating backup and using a drop in drive dock. Drives are stored on the shelf in an anti static bag. Not quite as secure as an external enclosure but a little more convenient.