In my first run, as soon asI finished with the early-game quest that required me to wear it, I parked the PA in Sanctuary and never looked back. I think it looks incredibly goofy (overcompensating, perhaps?) and is just an overall pain in the patoot to maneuver in. I completed the entire game without EVER using it again.
I'm now about halfway through my second run. The PA is parked in the farthest NW corner of the map. I have no plans whatsoever to retrieve it.
One of the many things that turn me off the PA (aside from looks and mobility) is the fact that the BoS folks use it so much. The sight of a bunch of them lumbering about wearing their Incredible Hulk Wannabe costumes makes me shake my head. Sad sacks, the whole lot of them. And the funniest part is they still need ME to come in and save them.
Oh and for the record, I use no chems, no boosts, no companions (not even the dog) and no big guns or energy weapons. Just me, my .44 (or sniper rifle) and some slightly jazzed-up combat armor. Matter of fact, the other day, just for giggles, I cleared an entire area of Super Mutants (including a couple of Legendaries) wearing my Agatha's dress and high heels. Power armor? Pffft. I'm powerful enough.