I have a single speed 2 HP Pentair Challenger motor that has been running for close to 30 years. I believe it's on it's final lap of the race so I'm in the market for a new pump. I've read several threads and based on what I've read I'm considering a more efficient multi speed pump. I have a pool and attached spa with no water features at 17,000 gallons. I have a Pentair FNS Plus 60 sq ft DE filter. I think I have around 52 feet of head. It seems like my equipment was maybe oversided for the pool? I have an additional booster pump for the Polaris and run the pool pump around 8 hours a day. Are there any recommendations on types of pool pumps (and pump size) that would be a good fit? Based on issues I've heard with the electronics of the variable pumps failing I would prefer the two speed pump over a variable.