I have a 21 ft hybrid (steel sided) above ground pool that I'm looking for a robot cleaner for. The E10 is $499 and specified as being an AGP robot. The Nautilus CC is $599 and specified as an in ground pool robot but will climb walls. There is so much conflicting information on weather or not the nautilus (or any in ground cleaner) will work on an above ground pool. Id pay the extra $100 for the nautilus if I knew it wouldn't damage my pool. The obvious upside is that it will climb the walls cutting down on my manual cleaning time. I don't care if it doesn't do as good of a job as it would on a in ground but I am concerned that it may puncture or fade my liner. Anyone with any long term experience with either the nautilus or any other in ground robot in their above ground pool?