The Mamba is a good speedo. After doing a side by side comparison, the biggest difference is the RS has a Turbo function that adds more timing at full throttle. That extra timing gives the RS the nod on longer straights. When I did this test the RS was adding about 60 degrees of timing and I only had the Mamba set at 40 degs max. Hope this helps.
Bob Walker Jr.-Sponsor's-
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