Every mountain style bike that I build runs a 2x10 drive train built on XTR shifters and XT derailleurs. I know the Shimano number schema and the prices haven't changed much with the recent lock down of regional pricing. Shimano components are commonly available, provide close enough ranges, and they work every darned time.
So far, I have built up.
Surly Karate Monkey.
Lynsky M290 Ti.
Foundry Firetower.
Foundry Broadaxe
Curtlo custom tandem.
I had one mountain bike with a lower end SRam drive train. The rear derailleur broke the first time out.