PhD or PE license? Graduate school or work to be able to take the PE exam?

which is better and what do most engineers do? Do they first work full time for X amount of years then take their PE exam or do they get their masters and/or doctorate then work to be able to take the PE exam? Which is better? Grad school going the doctorate route financially should be paid for and with a stipend, so which is better if there is just you and only you and you want to stay technical, meaning never go the business route?