Accept it for what it is and there is nothing to stop you from getting 10k miles on a single engine.
Like I said, I lost track long ago but I'm somewhere over 12-13k...never had any problem with breakage or durability.
The only reason I've had the head off was curiosity and cleaning. Had the carb off two or three times for needle adjustments and I grease and inspect the innards every two weeks. Other than that, it just gets ridden.
Other people think these engines are poor quality. I disagree.
The MATERIALS are poor quality, the engine itself is perfect for it's INTENDED USE.
It is not a fire-breathing race motor. It's a putt around all day on a few bucks motor.
Get a Morini if you want to run with traffic.
I'll wave as I putt past you while you're stopped at the next gas station! (or traffic stop
If more is better, then too much is just enough.
If you can't afford it, build it yourself.