Hi Thaddeus,
I’m glad the information here has proven helpful to you.
I don’t know the specifics of the materials and components in the Acadia but if you can find out the information listed here and post it on the forum then I’d certainly be happy to comment about the quality of the materials inside it or help you identify any potential weak links in the mattress, but Portland Mattress Makers (I think that is what you meant instead of Portland City mattress?) certainly makes some good quality mattresses and a two-sided mattress will also be more durable than an equivalent one-sided mattress that otherwise uses the same materials (see post #3 here ).
A pillowtop is a method of construction, and as long as the inner flanges and the gussets and the foams on the inside and below the pillowtop are durable and high quality and secured well, you should have no issues. I’m sure the people at PMM would be happy to show you how their beds are constructed should you have specific questions.
Phoenix