Years ago
PAMI used to run tests on combines. You can still read their reports online. They are quite interesting. I would be very interested to see modern, scientific, statistical testing of modern machines. Testing combines is very difficult, I've found, as so much changes with conditions. What worked last year might need tweaking this year. Companies talk about this or that feature on their rotor that does this or that, but truth be told, short of running specially-bred radioactive crop through a machine and imaging things with a scanner in real time, no one really knows exactly how material flows. You can learn a lot with a kill stall, of course. Mostly it's trial and error, like most things in life.
To answer your question, though, in my opinion, all brands of combines do about the same as far as efficiency and speed these days. Everything else is just a matter of preference, anecdotal experience, and most importantly dealer support. So no one can say their favorite color is clearly superior.
