So apparently the setup I use (the infamous 4.25 speed/4 accel one) is total crap because it has 1.75 traction. That's not me saying it, though. They say it's a death sentence on tracks like Dolphin Shoals and Sherbet Land, but to be quite honest I never really noticed anything in the latter (unlike N64 Sherbet Land in MKW with the Flame Runner, where yeah, you're fucked), and as far as Dolphin Shoals goes I only really feel the lack of traction in that one sharp turn before the !/$?$%ing segment with the pipes, and I'd say the reason why I struggle with this track is because I just suck at it. So as far as I'm concerned, traction's use is extremely marginal.
And even so, even if it was a huge difference maker on these two tracks, I'll gladly take sucking at them in exchange for better performance in the other 30. MKW had the same notion, where Sherbet Land and to a lesser extent Shy Guy Beach were misery for the best vehicles, and yet I don't remember anyone serious about winning using the Magikruiser just for these two tracks. It was Flame Runner and Mach Bike as far as the eye could see, Sherbet Land and Shy Guy Beach be damned.