Great info here. Thanks everyone. I've sent off an email to Marina to see which model they are recommending for my pool. The wife will hate me for doing it, but she doesn't wrestle with the original Kreep Krauley suction cleaner that we got with the pool 13 years ago. Hoses are starting to crack at the ends and I'll be darn if I buy those expensive sections. I guess my only concern is reliability / shelf life with these robots. I'd love to hear from anyone who still has an older unit that's going strong.