I've had one for a while now; used it to finish 4 kits over the course of a little over a year, but it's currently boxed up because I'm (hopefully) going to be moving soon.
You've probably seen that there are three filters: prefilter, middle filter, and carbon filter. The prefilter is good for 2-3 builds, maybe more if you don't have much overspray. I haven't changed the other two yet, though they're supposedly good for about a year. The carbon filter is supposed to pick up organics from the paint and thinner so that outside venting isn't necessary, although there is a 4" port on the back for that purpose; I didn't vent mine outside, and don't recall having any problems (most hobby paint booths only have the equivalent of a prefilter/furnace filter and are supposed to be vented outside, though many hobbyists don't)
The largest thing I painted in it was a 1/48 scale F-15, and that was sort of a tight fit. I would compare the noise to a cooking range hood on high speed.
I would strongly recommend getting the metal hood to go with it... it
has an acrylic panel in the top which allows light in (use a clip-on desk lamp). I purchased
the base from Bearair and the metal hood separately through Madison Art
Shop, but some places sell the base and metal hood together.
If you have any other questions, feel free to ask.