Keep the YS and learn how to tune it properly. They really are set and forget engines. I got my first YS 5 or 6 years ago and it was a well used 60FR and since then have switched to all YS engines even in my heli. If I ever have to fiddle with the settings on my engines I know somethign is wrong.

As for the pressurized fuel system, I sold my YS 1.40DZ because I prefer the pressurized fuel system. Use good fuel line and aluminum fuel Ts and also wrap your taank with a few turns of fiberglass reinforced tape and don't worry about it.

The biggest thing with the YS is to make your changes and let teh engine run 10 - 20 seconds to tell you what it wants. Most of the YS engines I have bought have been from people who said they could not get them to run right. To date, every single engine has tuned perfectly for me.

Just my opinion.