The 1st rod you have used to run in the engine must be replaced within 5 liters, some brands advise to replace the rod after running in. The Novarossi R7 rod has no problem reaching 5 liters.

Play is one thing to look at but the metal of the rod will get tired taking out the strength which you can not see, thats why it is best to change the rod once in a while even if the play is OK.

Racing or bashing has nothing to do with it. Bashers running a racing engine on long straghts do harm the engine more with higher revs for a longer time.