Those are all valid points. However, one can't compare F1 technology to a hobby glow engine. I've yet to see a roller follower in a model engine. Few valve trains for model engines have been optimized as they currently exist. There has been no demand for high RPM four stroke engines for cars. All of the engines which exist are based on the needs of model airplanes, power at low RPM <12kRPM. The OS S-C use only stronger springs and a new cam. The 40 additionally has slightly oversize valves. I don't think it's practical to grind a model sized cam with the kind of tolerances required for the aggressive opening lift curves being thrown around here. Pneumatic valve springs in models? The best we can hope for is forced induction like the patented YS engine.

The only way to improve the opening speed of the rotary valve is to increase it's diameter or axial length, which brings to light other concerns. Disc valves leave few options due to size constraints.

Two stroke model engines are virtually the same for cars and airplanes at the top end of the power/displacement heap.