I recently read a mind numbing study comparing the flow of propeller pumps (power heads) written in mid 2011. Ok, I will be honest here, we are all family. I read until my forehead cracked wide open when it hit my desk, and then I skimmed. Out of 10 +/- pages of charts, graphs, equations and theories and came to the following conclusion.

If you are in the market to upgrade and/or replace your power heads, compare advertised flow rates to actual ones, first. Then, look at the efficiency of each pump as calculated as the flow/power consumption. The only missing information that could aid in your decision would be the cost of the power head it self. I will leave that bit of investigative work to you. I compared the flow rate to the power consumption to narrow down my prospective list. I want as much f low as I can get with out feeding my local power company on a monthly basis. Once the list was narrowed down I looked at the cost of the power head and read as many reviews as I could find from real life consumers.

Good luck!