I generally keep it between 2000-3000 RPM. Engine sounds best there.
As long as I'm not lugging the engine I'm ok with it.
Mine is the 5-speed so I can choose whatever gear I need depending on the situation.
I learned to drive stick without a tach, so I change gear based on engine sound. Tach is just for reference.
I was on Vancouver Island all week and struggled to follow the speed limit as the vehicle speedometer was very difficult to read in Kilometers/hour. I knew 100kph is approx. 62 mph soo I was constantly mentally try to calculate the limit. No one in Canuck land drives the speed limit as far as I could see.