I own an iSpring under-sink RO system and it's been working fine for the last 8 years. I'm replacing filters every 6 and 12 months, and RO membrane every 3 yea

I own an iSpring under-sink RO system and it's been working fine for the last 8 years. I'm replacing filters every 6 and 12 months, and RO membrane every 3 years. I also replaced the RO tank once when pressure couldn't be restored. I don't think you're going to be able to sort through planned obsolescence schemes for water filtration systems. The money is made in the filters, not the under-sink systems. There are generics for just about every part.