At the time when the 9 speed 12-36 cassette was introduced, i set up a 1x9 commuter/utility bike with the 12-36 cassette and 38 t chainring. Since then, I've ridden the bike around 25000 km over all sorts of terrain, often with a pannier or two of stuff- including a couple 5 day tours. It is pretty hilly where I live. That gearing combination has served me well.