RE: OS 15 LA or Magnum XL 15?
Perth is to Brisbane as San Diego is to Jacksonville or Miami.
Don't fly much C/L these days, but do lurve combat.
Except for a popular event called "2½ slow" combat, plain bearing engines aren't used any more for competition classes of C/L combat. LA's are popular and adequate for 2½ slow. Like R/C SSC, the event is purposely constrained by limiting it to bushed 15's & no pressure feed. Within that speed constraint, pretty much any of the pb .15's will work OK, with the emphasis upon holding a reliable tune and easy starting.
R/C combat is something that simply hasn't caught on over here at all. It's possibly due to the cost factor as most everything is so much more expensive and therefore considered less as acceptably disposable. There are certainly nichés of competitive R/C, but they are just that. The sport flyer segment overwhelms the hobby. In what remains of control-line, most fly their particular niche and 50 to 60% compete in it.