I've got one. I had problems with the small circuit breaker cutting power off. Bought a couple of new ones from the manufacturer. Then I swapped a newer bulb for an older "second" I was saving and did something wrong because the contacts fried to the bulb socket.
Bought a new socket online for about 8 bucks and spliced it in. Paid a little more attention to installing the new $230 bulb.
Once in a blue moon it will trip the breaker in the box (15 amp). Otherwise, works like a champ.
If this comment jinxes it, I'm gonna shoot myself.
As for any noticeable degradation of time to expose, I can't say as I've noticed it. I switch between Aquasol MVP and Saati Grafic HU, which have varying times.