earlwb

I don't know for sure, but here in the USA the OS-Irvine engines cost more than OS engines do. It is the bad Euro to US dollar conversion rate that is causing the problem. Also OS engines have a bad Yen to US dollar conversion rate too. So even OS engines are expensive in the USA.
So if the Euro cost for a OS-Irvine engine is good in Europe then the engines would likely be a good deal and usable for newbies or beginners there in Europe. The 54.74 Euros for a 40MK 4 and the 67.49 Euros for a 46 MK4 and the 97.49 Euros for a 53 MK4 look like good prices in Europe (from Just Engines). I just don't know how someone in Europe perceives the Euro cost for a OS-Irvine engine.

The Chinese used to have a terrible time making good carburetors for the engines. the engines themselves would be OK, but the carbs would invariably be bad or defective. But replacing the carb with a better carb was very expensive and sort of defeated the purpose of buying the cheap engine. But lately the Chinese seem to have figured out how to make carburetors so the Chinese engines are working out a lot better now. So then the ASP engines are a reasonable choice now. But there is still some risk of getting a engine with a not so good carb though.

But then OS makes really good carbs that work great. I have not really read or heard about anyone having a bad OS carb. So in my opinion the OS-Irvine engine would be a good way to go for someone first starting out. Since the beginner type trainer planes use engines like the 40 and 46 engines, that would be a good way to go.