Before I bought my first GEBE (RedMax/Zenoah 25cc) I called experienced owners and got the lowdown.
The key is seating that cylinder in the breakin period, which IS accomplished a bit differently for this smallest weedwhacker engine, than on the larger 40 cc Tanakas, etc.
Nonetheless, I was told I would feel a burst of "horsepower" at about 150 miles, and this is true.
I was also told another burst would be felt at around 1,000 miles, and this happened to me in Oklahoma last year, right around the 1,400 th mile on the return leg from Denver. (It may have occurred earlier in Colorado, but the altitude played mind tricks on me and the engine).
There just seems to be nothing that could happen after that, so simple if you add the 50:1 oil, clean the lines/exhaust every now and then.
The plugs stay clean, my main personal engine, (the Denver one) has 4,000 miles minimum, and still uses the original plug.