The last few years of that motor, with the four valves per cylinder and 105/110hp were the best engine BMW put into a GS. Apparently they changed to water for higher power and emissions, but the hipster bikes still have an oil cooled engine and that is great, still legal too!
I looked into buying a nice one of those, but wanted proper cruise control and couldn’t find a nice one of the later years. The dry clutch and “car” gearbox make sense to me.