Fellow club member has the .50 size Sukhoi.... he flies it with a Saito .91... balance is perfect, and the thing is awesome (I traded him the kit... ouch)... The Saito is mounted inverted, and is completely inside the cowling.... One tip.... BEEF up the gear block on the Sukhoi... I think the gear is to long, and has a ton of leverage on landings..... he bounced it and BAM the gear block came out...... He quickly fixed it, and it's one of his favorites... which is odd, because his other planes are awesome... 33% stuff..