(This review was collected as part of a promotion.) I wasn't sure about this at first - I bought it to refresh and sanitize a pillow-top mattress. The cleaning head is pretty small and I also thought the steam didn't feel particularly hot. However, the more I used it, the more I liked it - I just had to do small sections of the mattress at a time. The water in the discard tank was pretty dirty at the end: I went over it once, let it dry under a ceiling fan and then did it again with plain water. The thing that I like the best though is how easy and intuitive the machine is to use and clean - very impressive! The unit also feels substantial although it's not large or heavy. I initially tested it on a pillow-top dog bed and it worked well with that - we have two large (shedding) dogs and I'm looking forward to using this machine on everything they sleep on!