The vast majority of the vehicles here are Japanese or Korean, with a sprinkling of Brazilian, German, Mexican, US, and maybe a dozen British Land Rovers. About 50% are diesel. Actually, 50% are used Japanese cars and trucks that have been locally converted from left-hand drive to right hand drive. From what I have seen my opinion is that the Jaso standards are behind the API and ACEA. These vehicles come with about 130,000 Km on the odometer and are smoking, almost immediately in need of rebuild. When taken apart they have 3 times the varnish and sludge as the others. Of course I do not know exactly what conditions they were used in, but 6 to 8 year old vehicles, from Corollas to medium sized trucks should not be in that condition. My 95 4Runner 2.8 diesel has run entirely in Bolivia on the latest group I API spec I've had since new. at 100,000 km it was spotless. Last year my accountant bought one ot the "transformers" 1994 4Runner used in Japan. It has 120,000 km and he had to rebuild the engine as soon as he got it. The inside was covered with varnish and sludge.
Of all the standards, I believe that ACEA is far ahead of the API. Look at seal tests and NOACK.