personally, I prefer to launch on high rates and switch to low rates for high speed. I've tried low rates and it's more than flyable that way from launch to touchdown.
as far as best setups, Dons is the best by far. for the money, quality and plug and playability, you can't beat it. the metal fans are cool, but they don't belong in a foamie IMHO. the biggest reason, is that they sink the heat straight to the airframe, which is why I don't use them on foamies. weight can also be a factor too. not saying don't use them, just giving reasons why I don't use them for foamies. heat and foam just don't mix well.
I can also tell you this much...............my Dons setup was way less than any metal EDF out there and it performs on par, or better than my metal fans. you just can't beat it. plus, Don stands behind his products. I will continue to support him based on that selling feature alone.