RE: Which sounds the best?
The Saito .56 and .65 sound great in the H9 Cub. Saito and YS each have very unique sounds. OS and Enya sound similar. Thunder Tiger seems a little louder and raspier than the OS and Enya. Of course you could use the Saito .90 flat twin and be even more unique sounding! At idle they sound like a top fuel dragster.