Been running 2 Nero3's in my RSR Nano for over 3 years now, one has never had issues, the 2nd had a few but they've cleared up now. Basically, anytime it stopped I'd pull off the impeller, clean it, sand it down a bit with a modeling sand stick. After a few months its hasn't locked up in 2 years or so.
Have a 3rd Nero3 in a IM40 that hasn't had any issues in the year it's been in there. I really like them and would buy more as they aren't overly expensive, have a great app and seem reliable with alittle effort.