Props. The DJI Kit props aren't very good. They do an upgraded one the 10x3.8, which I find pretty good. The Graupner e-prop 10x5's are excellent though. You may want to go 9x5 as you are mixing 3S and 4S lipos?
I'd stick with one battery type initially though, get a couple of packs the same. You may be having to adjust gains between different pack/props combos to get the best flight control.
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Team Yokomo - YZ-2CAL3 | YZ-2DTM3 | YZ-4SF2 | YZ-2T | YZ-2DTM Worlds | YZ-2DTM x2 | YRX-12 x2
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10electric | Batley Buggy Club | YORCC | RHR | MB Models
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