In trying to level the playing field and make just the thumbs that are the variables I think saying all 4s 2500 mah 20C batt are the same is like saying all pigs are the same. I think there is a very large variable in batteries and just because a battery says all those things and cost more than any others doesn't make it the most efficient, highest capacity, or highest amperage draw battery of the group. Even within the same manufacturer you will find wide variances and a knowledgeable person will find the best battery and will run it appropriately. [X(] As usual the folks that do their homework will be running at the front of the pack and those that don't will be also ran's. I am not opposed to EP Q 500 racing as I like my elec planes. I like the turnigy equipment and the Zippy family of batteries. I just ordered 4 GS Q 500's and plan on making one of them electric. I was thinking of the SK 42-50 motor which weighs about 2 oz more than the 35-48. I think if you try and be to restrictive the people you want to come out and fly won't because they have to be to specialized. You might have different classes with a breakout time to move up to the next faster class like the RCPRO Warbirds use and keep the equipment restrictions to a minimum.[8D]