I'm running a very power hungry 1200 with its stock brick PSU (A600/1200 unit) and the only problems I had with my setup was a VERY hot PSU, which soon changed once I added a fan to it. It now runs cool and the fan is silent because I used a 12V fan from the 5v supply line. It's near the back of the brick case pointing towards the heat sinks. I used an ATX PSU before that, but was very noisy and UGLY, so I decided to use the original supply instead.
It's powering apollo1260/66 32meg, FastATA with 2.5" hard drive, clockport prelude sound card, 12v high rpm fan in 1200 case, squirrelscsi interface, and floppy drive of course. I've had no issues with power whatsoever, and have been using this psu in this configuration for over 3 years now.
