I like them, but since you've already got a 500 I'd probably just pick up a couple of upgrades for that one and hold out for the 1200. The 500's hardware is much more reliable and easy to repair, and RAM/hard drive combos aren't too hard to find. The 600 would be more worthwhile if you planned on adding an accelerator to it, CPU upgrades are a bit harder to find for the 500.
