My old P300 is still running strong after nearly 5 years (and I bought it used).
I don't run over 100 watts of equipment on it, so it does run hot when near 100 watts, but not dangerously so. I've only overloaded it once where it's thermal protection kicked in and shut off. But I hooked up a 46" DLP HDTV to it, fed off of a UPS battery, the absolute most torturous test possible. So, I definitely found it's limit.
I am currently running my Emotiva DMC-1 Pre / Pro and Smyth Realiser on the P300. I also use it to switch power off, since the Emotiva DMC-1 never actually turns off. I measured exactly the same amount of power used regardless of whether it was in standby or on. What a waste. That said, the P300 uses about 20-25 watts on standby. There is a good old power switch on the IEC inlet in the back, so I can shut if off completely when I'm not going to use it for extended periods.
When I have the chance I'm definitely upgrading to a Power Plant Premier, since I'd like to put the rest of my home theater on it, including my 50" Pioneer plasma TV, which uses up to 500 watts, and about 250 watts on average. It uses less than one watt on standby, which is remarkable.
I know PS Audio offered a Power Director and now their P8000 and P9000, but I don't need that web interface. I hope they add switched "zones" or individually or grouped outlets on the Power Plant Premier in the future. I'd like to be able to shut off power to components, and leave others on.