There is at least one other option that I am very familiar with and close to. If you look in the Pattern Forum you will see my thread on the OS33GT. Some Europeans are also using the PTE36R in Pattern applications. I also have a PTE36R and that will go into a Vanquish conversion from electric

We finally have truly usable gasoline options in Pattern. These engines have terrific top ends but most importantly, have lots of grunt in mid range, where Pattern pilots like to fly.

To get the most out of Pattern gassie you should also consider soft mounting and using a pipe on the model. It's a sound similar to well tuned glow 2 strokes we're familiar with such as the OS140RX and Webra 145/160.

BTW- FWIW- My OS33 piped set-up uses the same props as YS170/175 do and turns these at similar rpm. If the YS170-175 are the defacto standard for glow Pattern, these gas engines are really worth a good look