I was referred over to this website from another pool site. What a lot of great information. I am about to do a pool remodel (luna quartz resurface, new plumbing and surrounding decking) and the PB suggested a SWG system while we were at it.. In doing research,thanks to this great forum, I have decided on the AutoPilot (DIG-220). I have a 19,000 gallon pool and have read that is more practical to "upsize" the cell. The smallest cell is the 35K size. Do I stick with that or go for the 42K size? I don't mind spending a few extra $$ if the system will work better. Thanks for the help and looking forward to swimming in a SWG pool this summer