If I ever do get into racing it will be so far in the future that I would have either already upgraded all essential parts to race quality through the natrual processes of breakage and wear and tear, or will buy a car at that time specifically for racing.
Whenever I price out a kit, i tend to migrate towards higher end components to complete it and the price ends up well over what I need to spend for a startercar. Plus a car that is not already race ready gives me the opportunity to learn more about maintaining it as I start doing upgrades.
What I don't want is something with known reliability issues that will cause an almost immediate repair cost in the hundreds do to faulty or cheap engineering.