It depends on if you are in the rackmount market and how mission critical your system is.
if you are using for personal use, I would say go with some what of the cheaper yet somewhat dependable stuff ie..
emacs (zippy), delta, bps, sparkle
There are high-end 1u 2u power that we use at work, I have had almost 5-6 yr old psu's that are still running 24/7 without a hitch, but hey it isn't my money and i don't have to run my computer 24/7 for that many years
