Like several people have mentioned the price difference between true acid-free boards and regular coated boards is neglible - and considering how much of a difference it makes from a conservation standpoint, it seems like a complete no-brainer decision to me. The switch from polybags (which, btw, are never archival-safe either, no matter what the manufacturers claim) to mylar, however, is a bit trickier - there's no question that polybags degrade over time which, in turn, produces harmful chemicals that also hastens the comic book's natural aging process, but the actual physical effect this has on a comic book is much less severe than the one caused by a non-acid-free backing board.
I made the decision years ago that every single book in my personal collection - whether it was worth $1 or $1000 - was to be stored in mylar with a true acid-free board. Considering I own about 13,000 books that was a bit of an undertaking, but not having to swap out the bags or boards again made it worth every penny. Not to mention that books in mylars just look
With a regular coated backing board it's actually both - both the comic book & the backing board are happily off-gassing acids inside the semi-sealed environment of the comic book bag, and therefore speed up the natural aging process of both items.
A buffered, archival-safe board, however, is meant to address those very issues - not only is the board itself acid-free (and therefore doesn't contribute to the acid build-up), but the calcium carbonate buffer also helps to absorb & neutralize the acids that develop in the comic book as it ages.
There's no question that the environment a comic book is stored in is just as important as using archival-safe products (oxidation is part of what causes paper to turn brown), but using the correct storage products will go a long way towards protecting your book from environmental factors. I personally never use open-top mylars unless it's a double-bag combo.
Thanks for taking the time to answer my questions.
It's greatly appreciated, I just recently changed the bags and boards. Had I known that the E.Gerber boards were the same price or even similarly priced I would have purchased the E.Gerber Brand.