Do consider the Evolution 46 or 52 two cycles
The 46 is more powerful than my OS and supertiger 46 engines ( more like 50-55 power )
These engines just never caught on , but have brute power for there size , are true chrome cylinders and built for the long hall
I bought one at a swap for 25 dollars and was amazed at the power , owning many OS engines of all sizes and series
Building and flying more than most for 24 years , so i was surprised
The engines are around alot in the 50 dollar range and originally came on a HORIZON trainner as best I can recall
Is truly a great 46 if it was 150 dollars , and one of the hobbys well kept secrets , as they have never become popular for some unknown reason