I am a new owner, year or so of a YS 63. I wished I had got one for my second engine. Once you know the basics they are not too bad. I have had an air leak on a 2 cycle drive me nuts before, what would be different about a four stroke?? One has to learn the ropes and it does not appear any harder to me on the YS.

I am not setting a fire here nor wish to offend anyone, the YS fired right up out of the box with little or no messing with and I have not had a moments problem. I can't really speak for the larger engines.

just my 2cents