I love YS also, but I wouldn't recommend them as your first 4-stroke, you'll get too spoiled too quickly, and while they are no more difficult that any other, they ARE a little more complicated, so I would just avoid them the first time out.

I also have no experience with Magnum, ASP, or TT, and I haven't used an Enya in many years, so that leaves my experience with OS and Saito. Of the two, I prefer OS, But it's a Ford/Chevy thing