I'm looking for some advice on tire weight and how much a heavier tire will effect my power. I have an 09 JKU 5.38 gears with 37x12.5x17 BFG Km2s. The listed weight is 74 pounds. I'm in the market for new tires and have been reading good reviews on the STT. My biggest concern it they are 9lbs heaver per tire. How noticeable will the weight be in performance? I like the look and price of the STT and the KM2 is on back order with no foreseen date to be available. Thanks in advance for the expert advice.