CaptRon, the ONLY Rv'ing deal I've found better than PA, is the America the Beautiful Senior Pass, $10 for Lifetime, but you are spot on about PA, we've been members for 8 years and have saved a lot of money using it.
"some parks limit the PA discount to weekdays or not on holidays or limit the PA discount to 1 or 2 days only. These restrictions can be worked around and they're spelled out on the PA write-ups so you should know this going in."
this part of your post seems to be the biggest gripe of nay sayers, but as you pointed out, IF you read the restrictions of each campground, (some have no restrictions) you should have NO surprises.