Input highly appreciated! I am looking for a Swim Spa with a strong smooth current for swimming. As I would like to run it outside year round in a cold northern climate I have not looked at endless pools or swim ex. The 2 spas that I am choosing from are the Michael Phelps Signature XP (pro was not available for test) and the Hydropool Aquatrainer (Olympic version with more power). My experience from the wet test was that the MP Signature had a weaker current and slightly more turbulent. After wet testing the 2 the result was a little bit disturbing as the Aquatrainer was both stronger and the current smoother. This seems to go against most of the comments / information online that claim propellers create the best and strongest current. My question is if there was something wrong with the Michael Phelps unit I tested or if you really have to try the XP Pro to get the better current? All input appreciated including suggestions for other SwimSpa Brands!