We had a couple of pop ups and then bought a used 2003 Starcraft hybrid and we love it. It was like brand new when we got it 2 years ago, and we've tinkered with it and made some changes, etc. We have had a tiny bit of condensation issues (when we had a campout sleepover for our daughter and there were 5 girls on one end) but other then that if you leave a vent cracked or the tent end fans going, you are good to go.
If you are looking for used, make sure you inspect all of the tent ends and really smell around for mildew. Check the floor for soft spots all over.