I have two, one (40GB) was purchased a couple of years ago when my must-have approach, cost just below £200 with a complete, ready made, smart looking Amacom. Later I found it has a Western Digital HD inside
Last month in a hurry again, I bought a nice case and put a spare W. digital (20Gb)inside that. The case including power supply and USB leads cost £35 at a local shop.
Both outfits have their own power supply, both have behaved reliably and without fuss or appreciable noise when running.