You said drive it hard sometimes. How many times? You push any car no matter if it was meant to rev up to 10,000 RPM's and that will wear your engine quicker than driving like grandma shifting at every 3,000 RPM's. Of course it's going to wear the engine and transmission more. How much? I can't say. Depends on if you hit the rev limiter every gear when driving or once or twice a day or week. Once in a while is not bad with scheduled checkups and maintenance. Other than that I hope your race sponsors give you another engine. If you can't shift properly either, especially spinning at 8300 RPM's forget it. Wear and tear. Toyota builds a tight reliable car, but over time you will have some major issue. There are already some problems with "lift bolts", synchros/transmissions, and mis-shiftings so be careful.