I have a fight scheduled where I can't get to the airport as early as I would like, I don't want to miss my flight and I want to know if purchasing premier access could be worth it.
There is a priority access lane at the security checkpoints used by UA. DTW & UA are also on the TSA-Pre list. That would be the better bet. Get pre-authorized by TSA and go through even quicker than priority.
One thing to think about, however, is that TSA-Pre gets you through security faster and that's it. Premier Access gets you boarded quicker (usually), or "before the unwashed masses," as the premier forums all call us regular folk.
(Personal Op-Ed here: I wouldn't take premier access if you gave it to me, or at least won't use it. I don't like planes, and prefer to sit in the lounge until the absolutely last minute, but that's just me.)