Get familiar with your instrument. It's yours. Adjust it to your liking. If you can't and don't have the gumption to do the research/obtain the tools, have someone else do it that you trust. If you don't like the change, have it returned to the way it was or change it again. Don't base your assessment after an adjustment on a few light string plucks at the service counter, play the thing for at least a few hours at home and then play a gig. Whatever feels/sounds right to you is correct for you. There are plenty of resources available to learn the basics of setting up an instrument.