After more flights than I want to remember, my original LA 25 has worn out the P/L.  Lots of combat dirt, and lots of hard running.  When I tore it apart, it was definitely worn.  The inside bottom of the sleeve had a nice big gold patch on it where the plating had worn away.  Combat buddy Roy said he'd had several liners wear away to the brass, but they still ran OK, as long as the fit up top was good.  This one wasn't.

Swapped in the P/L from the stunt 25.  It has much better compression and starts and runs much better.  Interestingly, the newer liner has already worn down to the brass below the exhaust port, on probably no more than 100 4 cycle stunt runs.  Makes me want to pull a Zambelli, and bore the case out to take the Brodak 25 or Thunder Tiger 25 liner.