I recommend a wide band O2 reader.
It will tell you exactly if you are running to rich, too lean & everywhere else.
Get the best A/F ratio for mileage.
It will tell you if you have too much accelerator squirt etc.
Having a WB reader really speeds up the tuning process & takes the guess work out.
For the most part, you do not need to take out your spark plugs & try to read them.
They are affordable & no good reason not to have one.
MBHD