In my house, I have measured the voltage at my outlets on numerous occasions. While it's mostly regulated fairly well by the transformer, several houses share it. I usually get 121.3V but I have seen days where the voltage has creeped up to 123.1V
If your wall current is measuring 110 it is within the rang of the previous setting so it should be fine however, as Floyd mentioned, and especially if it seems to be functioning ok, I would agree with him in the sense that 115-127 is the most versatile setting.
Most of us aren't going to carry around a volt meter from place to place to check (when traveling especially) and you can be guaranteed that at that setting, you really can't go wrong unless you plug it into 220/240 and to do that you would need to change the plug out.
Im not sure about your area but at the 100 to 110V setting, If you happened to hit an outlet in a different area that's supplying 120V and you had it on 100-110V I would feel uncomfortable with that and not knowing about other circuits elsewhere in my area of travel would bother me personally.
So my vote would be to leave it there because I seriously doubt you will notice any performance increases by changing it and the setting it is on is a safety margin for an area that may be hitting higher numbers.
