I havent used one myself, so I dont know how easy they are to disassemble and clean, but I would think if you cleaned it at least every other week or once a month, you wouldnt have too much of a problem.
I've seen ppl use PVC and pipe in humidifiers, and I thought that was a neat idea, Ive also seen them use the personal misters available in sporting goods stores and retailers to mist the cages.
One thing is for sure, Im getting carpal tunnel from misting 5 cages 2ce a day!