they tend to be quite noisy so i wouldnt recomend them for some one whos gonna put it in their bedroom. at night i used to turn mine off but crickets kept crawling into the hole where the water comes out and blocking it up. so it really needs to run all the time.
Not had any problems with mine whatsoever.
Only feed hoppers (so too big too get inside) or enough crickets that will get eaten straight away. No chance of anything getting stuck inside.
The 'noise' could be due to the pump vibrating. The little suckers on the bottom of the pump are not that good. All I did was put one of the little white rubber wedges (that you can buy to keep viv doors shut) in between the pump and the waterfall. Not had it vibrate since.
The only other 'noise' is the sound of running water which I quite like.
I use a fogger in mine and between the two units they have stabilised the humidity in my viv to almost perfection.
I was looking at them but the more i looked the more synthetic and artificial they looked to me... and heard they clog easily and the water runs out quickly. I made my own with a pump, rocks, tubing and aqaurium silicone!! it looks great (although out of action at the mo!! haha)