I agree with most of what has already been said, however I must add that I have only adjusted valves once - ever (and I have been using 4-strokes almost exclusively for over 20 years)

I have also never used a tach to tune one. Can you tune a 2-stroke? Then you can tune a 4-stroke.

About the only difference is that a 4-stroke does NOT like to run lean, so if you're adjusting the needle, and you can hear that it is starting to get too lean, BACK OFF (or you might spit the prop off)

And ditto on sticking with OS and Saito your first time. Although both are more user friendly, OS seems easier to tune, need much less break-in time and spit MUCH less slime on your plane