This depends on whether your car is obsolete, or still competitive after a few years. Honestly, no one class is for everybody because we all have different reasons why we decide to go racing. For some it is because they are really competitive and driven. All of us, to different degrees, do it for ego. For those who love to work on cars, a class that allows them the ability to build a better prepared, faster racecar is what motivates them to race.
Some drivers just like to drive, regardless of where they finish.
Me, I m the competitive type. I do enjoy working on cars, but only to a point. I also like the idea of driving a purpose built racecar because of the way they look and handle. They tend to be more responsive, and to my mind, more fun to drive. I am also concerned about safety.