Go to http://www.poolplaza.com/ for a good explaination of 2 speed pumps and also some pricing comparisons. Its a good place to see a whole bunch of pumps in one place. My PB talked me out of a 2 speed pump, one of the dumb things I did. Same reason as your poolstore, too expensive, never used.

So, I now have a multi-speed pump that I installed myself this year. Since we use solar for heating, our pump runs during the day when we are swimming. The 2 HP Hayward Superpump was WAY too loud. I installed my pump so that it goes to high speed when solar is on (I have a large array of panels) and low speed when solar is off. In low speed, you almost cannot hear the pump, even though it is still pumping close to half the amount as high speed, and the electrical use is about 1/4.

PLUS, many states (such as CA) have energy rebates and soon will REQUIRE 2 speed pumps, so you might look into that as well (unfortunately, NY does not have such a rebate).