Who knows the industry rankings for various control valves and instruments?

Rankings? It’s hard to say; each one has its own advantages and its own unique features

Is ranking interesting? What is there to compare it to?

There are some survey rankings in the Control Valve Information magazine; I’m not sure if they will be useful to you. .

Does the original poster think this kind of ranking has any practical meaning? If valve manufacturers were to conduct market research on their own, any manufacturer with even a modest level of reputation and scale would claim that its valves are the best. Think about it: you pay for a market research study, and if it doesn’t deliver results that satisfy you, would you still give that research company a good payment? Don’t believe those manufacturers’ claims of being number one in terms of technology, quality, and service; if that were truly the case, such products would surely hold a monopolistic position in the market. Ask the Ministry of Railways; as for which entity has the highest volume of railway transport, it’s definitely the Ministry of Railways. Isn’t it obvious? But if you go and ask those large freight companies who is the leader, they will probably all claim to be the leader; there can be conditional factors regarding a certain region, certain industry, or certain type of goods.

Yes, OP – it’s not a matter of one being better than the other; the advantages of each manufacturer are relative, and each has its own strengths. Any ranking can only refer to sales rankings for specific types of products.