The best set-up is the one removing as many variables as possible. Using a protractor and digital scale will leave VTA as the variable. That is more reliable and faster than guess work.
Digital scale (reliable enough for our purposes) from DealExtreme are less than $20. Protractors are free from vinylengine.com.
Digital scale (reliable enough for our purposes) from DealExtreme are less than $20. Protractors are free from vinylengine.com.