RE: aaaaaaaaaggggghhhhhhhhhhhh why??
I had a really naff engine when I built my first Raptor - think it was called GMS - and could never set it up to be consistent. Now I always stick with OS which have always "flown out of the box" but have a TT that I came by and it runs OK but OS is the best for me. I like the reliability that they deliver and I'll go 37 as soon as I can afford it (fraid money is an issue for me).