CC and 8/9xl

Since you all think I should go sensorless, I thought of the Mamba ESC, and a 8 or 9xl? Ill be running 14 cells. I want more runtime then speed. Top speed, runtime, gearing? So the ESC is rated to 12 cells, but if I get the external 6v BEC it should run fine, correct? If I had metal diff cases and diff holders, the stock diff gear should be fine? What motor would you recomend? 8xl or 9xl 540c. Would I be able to adjust all the settings like, torqe curve, drag brake, brake, and all that good stuff? Would this be fun to drive?

Also how is the fastlane chassis? Where do you get the battery hold downs?

MM ESC $140
8/9xl $ 90
6v BEC $ 40
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$ 270