I do think that there are advantages at every price point, and some of the low end kits are complete junk. But in some cases you can get a kit that has the same geometry as the premium kit. Cost savings come in by use of cheaper materials. X-ray, Serpent, Yokomo all are high end companies that offer a kit that shares geometry with its flagship kit and in most cases is upgradable using the same parts. On the lower end of the spectrum we have Spec-R, with the R1 and S1. Both are the same kit, but the R1 uses better materials. Even with that being the case, you will see racers that will replace broken c-hubs using X-Ray parts. That is a testament to X-Rays quality. Still many find value in the lower end kits, and find them to be all they need for club racing.
I don't know why but this reminds me of Josh Cyrul when he went with TOP, a mostly unknown company at the time. But Josh designed them a great car and put it on the map at some good sized races. That's another story.