Don't worry Sainted it's a very interesting topic. I started out touge with race suspensions too because: A) On paper they increase grip and B) With the amount of adjustments you can make to it you can definitely create a cornering monster. However I was convinced to try out stock and sport suspensions on some cars because of Wilson. I was skeptical at first, obviously because the stats say they're worse, but I managed to shave off more than a second off my lap time instantly.
The thing is, SOME cars have stock or sport suspensions that feel like fully tuned race springs. A great example, the 86, has a terrible stock suspension, a street suspension that is WAY too soft, and a default race spring setting that is too stiff. The sport springs, however, work marvelously on that car (as they do with 95% of the cars I've tried). So you can either install sport springs and save yourself 1 PI, or you can spend hours trying to create a race suspension setting that will probably just match the sport springs anyway.
I'm not saying race springs are inferior, but I AM saying that unless you tune them perfectly to your liking they will not be superior to plain sport (or sometimes even stock) springs. But if you get the tune right they probably WILL be superior.
On a relevant note, my best time on the downhill is a 4:32.6 in a Gen 2 MX-5 with sport springs. MiNdChArGeR's best time is a 4:31.7 in a Gen 2 MX-5 with race springs. The different spring setup between our cars is the probable culprit of that 0.9s gap.