Personally I have given up on them. I had a large living room, dining room hall, foyer etc to paint.. so I got one. The first time I used it it went well. But.. the clean up was unbelievable. And the clean up is very fussy. I thought I was meticulous..but somehow some water must have gotten in the vaccuum hose.. and the next time I used it the unit wouldnt shut off. The paint kept pumping, and pumping. It was like a comedy scene from the 3 Stooges. And I pride myself on being very thorough with my tool maintenance.
I found it too time consuming and fussy to clean. Its been sitting in my basement for 5 years. Want it? I found normal rollers and brushes to be the most reliable.