About two months back when I was first commissioning my Duet WiFi I was reading about power supplies on the Wiki and dc42 had a note in there about how cheap power supplies fail more often or something to that effect. I thought "wow I must be lucky I have two of them that have been performing great!". Less than 2 days later I turned on my printer and POP something blew up and the whole thing shut down. Sure enough the power supply went out (never did figure out what popped as I took it apart and nothing had exploded…I was a bit disappointed). Fortunately I was able to swap in my "spare" but immediately started looking for a replacement.
I settled on the relatively new and slightly more costly UHP-350-R it has no fans, is utterly silent, has remote voltage sensing, and a super attractive footprint. I have to say its been pretty awesome. I basically just leave my printer "on" most of the time now as it makes absolutely no noise whatsoever. I have to admit its really nice to not have the power supply fan increasing in volume every time I turn on LEDs, or as the hot-end heats up.
Obviously 350 might not be enough umph for some people as I am using an A/C bed off mains behind an Opto22 and not a 24v bed, and currently am only running a single extruder; however I calculated that with dual extrusion, motors at full tilt, 4x the LEDs, 4x the fans, adding an LCD, two additional PT1000, and a DuEx expansion I would still be WELL under the 350W that this thing provides. Right now the damn thing doesn't even get much above room temperature during the course of a multi-hour high-temp (PETG/Nylon) print (in fact the printer is has been sitting idle but on for a day and its the exact same temp as if it had been printing non-stop).
I purchased mine through Arrow since they had free overnight shipping but I found several other vendors as well, it cost me a bit more than some of the fan-cooled versions but to me the silence was worth the price. Picture of it mounted for reference:
Just another option for those interested!
-M