I have a 38K gallon pool with a hot tub flowing into it. I have 2 Jandy MHPM 1.5 pumps that are 9 years old, one for the pool and filter, the other circulates the hot tub. I new to replace one of them now and the other pretty soon. What pump would you guys reccomend to replace since it is discontinued? Secondly, should I switch to a variable speed pump as I hear this may save on electric costs?