If that news was published a week ago I do not think any true experiences are known yet....

A guy I support with made parts and knowledge did use this year to test other brands after the quality of OS did let him down at the beginning of this season. The R9R was one of them. It was a hard to tune engine but there are more complains about the used carburettor with as example REDS engines (look up the offroad topic about REDS). Switching it to an OS or the old always working Novarossi did improve the tuning but still a rich low/mid range did exist. This is a complain more people have...
After measuring the timings I had an idea how to solve that but they ditched the engine already.

The crankshaft is super wide timed from which we know with the OS does work but the transfer and exhaust ports were very low. So with the large crank window it was made to get in a lot of fuel but due the low port configuration probably (my theory) not made to get it all out again. Also with a huge stack of headshims there was enough room to raise the sleeve with a 0.2mm to get more in range with a better port timing as used on many other engines.

I may hope they did solve the issues with the X9R. That they are searching/experimenting may be clear as I have seen 3 different R9R engines over time.