TBH I think the likelihood of having problems are far lower with a server PSU vs a consumer one - the server PSU's are MUCH higher quality and in turn have much more consistent power output.
That depends on the consumer PSU... most of the high end ones are industrial grade. I use all consumer units... then again, I review these things and have access to the really high end stuff that costs most folks a fortune. For most people, the server units will be more cost effective. I wouldn't even look in the consumer market if I had to actually buy PSUs.
I also try not to run any units that have output devices under the main PCB - these usually require heatsinking to the housing, and if you have no airflow to said housing they tend to heat up more than they otherwise would. I prefer units that have the output parts and heatsinks directly in the fan's airflow, and have a way to disable any fanless modes. Running these things 24/7 at high output is demanding - they must be kept cool and well ventilated. And at 240V, if possible.