Mike - Be of good cheer. A couple of months ago, there was a string on RCU about the O. S. .91 becoming extinct. User feedback was so strenuous that the engine was placed back into O. S. factory production when the order levels call for a run. My feeling is that the engine will be around for quite some time. There will always be a group of modelers who want to fly jets but for one reason or another are not willing to put the money into buying a turbine. Dynamax, Ramtec, and Turbax ducted fan setups offer a less expensive (than turbines) way to get the thrill of flying a "jet".

As always, though, this is just my opinion based on recent trends. Your mileage may vary.

DFF