I suspect the "UR" means up-rated for 1hp. If so, it is not as powerful as the Superpump, which is full-rated for 1hp. So it's not a comparable pump, it's a smaller, less powerful one. Which is why it's quieter (but only on full speed--on low, the S/P barely hums so quieter than that is meaningless.).

That doesn't mean it's bad--42-44 gpm may do nicely. Will it lift the water as high as you need? I don't know. The folks who understand feet of head may have a better feel.

I'm not an electrician, but I believe that 220/240v pumps are more efficient--electrical-usage-wise. 150V must mean 115 or 120v.

Basically, the Whisperflow is what is described as an Above Ground pump, but the SuperFlow is DEFINITELY an In Ground class pump.

Here's how I have mine hooked up. It's just sitting on the paver: