Pump Speed - Single or Dual?

We will probably have to replace our 12yo Hayward 1.5HP Superpump when we open this weekend. It died just as we were closing last year & was making terrible noised & shutting down sporadically just prior. I've googled all around this forum & the internet & gotten myself more & more confused.

Is a dual speed really more energy efficient and quieter than a single? I've read conflicting info. (As for variable, that's out of budget). If we did replace with a dual speed, what HP would we need? I read something about uprating??:confused:

We have a 27K in-ground vinyl with 1 waterfall; Hayward sand filter.

My pool is about the same size and I was researching this very same issue earlier this month.

I would get the same size in a dual speed. The dual speed adds about $100 and each 1/2 hp about $20.

CA & FL require dual or variable speed, so I would assume the energy savings are significant.

Luckly my motors still working.

I had a Sta-Rite dual speed pump (1.5 HP high, 1/2 HP low). The low speed didn't really work that well. In many cases the flow was so low the pump lost its prime and stopped working. I eventually opted to keep it running on high whenever I operated it. Plus, installation was an annoyance as it took us a few tries to find someone that could wire the thing correctly. Even with Ben's explicit instructions I got a few puzzled looks. The electrician finally figured it out. Your mileage may vary but I won't buy another 2 speed pump going forward.