I agree, the 370Z isn't the best car for the track. However, it is undeniably one of the best for its price range. Sure a GT3RS would destroy it on a track, or lotus exige, but if you are looking for a great car both on and off the track for under 40k, you'll have a hard time finding a better car than the 370Z.
If you want something purely for the track, and for cheap, you should look at ordering and building a Caterham.
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