In my experience the OS engines have offered nothing over their DLE competitors. A mate of mine had a OS 33GT but after about 500min of running all hell has broken loose. The liner appears to be loose and has shifted. The engine deasticked and cost him his PRC Yak 54. He is now having trouble getting repaired because its going to cost him. The local agent does not offer a warranty on the engine, it has to go back to Japan.
None of my DLE's has missed a beat.
The RCEXL CDI's are used by Saito, OS, and appear to be more reliable than the units offered by MVVS, DA, 3W and other high end high quality engines.
to me quality is what gets you to the flying field and allows hours of enjoyment, not top dollar.
I appreciate the attributes the expensive engines offer ( I have a few myself....) but the DLE's are very hard to overlook simply because they're from China