One of the few (very few) places I would disagree with Doug.
I would have an alignment done FIRST (yes, assuming an alignment is needed). I would not assume that the tech would loosen the Safe-T-Plus to take it out of the equation and then recenter it (which often takes several tries)
Because of the centering force of the Safe-T-Plus, it can be used to mask alignment, brake or tire issues. It can "correct" for a pull to one side that should be addressed by correcting the root cause, not using add on device to mask/correct it.