I have actually used these in a few low-power noiseless builds I have done for people and they are excellent. If I ever get around to building a MiniITX Macintosh Classic, this would be my only choice.

Just be sure to spring for the 192w 4-pin power supply version, even if you only plan on consuming half that. It will give you ample headroom for extra future components, the AC adaptor will run much cooler and last a lot longer, and the 4 pin plug is less prone to coming loose.