You can never tell.....

Factories are changing materials constantly and the quality and ofcourse with it. The running in proces and when starting up the warmup proces is very important for the lifespan. Oil is also important, a drop more can do a lot but will also take away the driving time on 1 tank, thats why most high end fuels have 8~9% oil. Also fuels are changing, you will never know what you will get next time and sometimes there is a batch damaging the engine....

Gearing wil help.... large gearing gives less top rpm saving the engine but it can give more stress on the internal parts, for sure the rod. A light gearing will give more RPM and also more stress (higher G-forces at a high rpm) and the higher rpm can give loss in the lubrication, you need to find a middle way. So going for maximum performance will always affect the lifespan.