Well I had one of the original Novak 4.5's with standard shaft, and it never gave me any troubles. It was an insane speed run system. The newer one has the lipo cut-off, and from what I've read on other boards, Novak has increased the voltage 5s lipo's. I probably wont go over 4s, but 5s is a nice option too. Some PPL like Novak, some dont, I personally have had good luck with them in other offroad applications. And its alot cheaper than going the MGM/Neu route I did with my Emaxx

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