As you say yourself though they're not free, BAEC is not the program for you if you want cheap flights and a quick scan here would've told you that before you took out the card.

If you want a J seat for the price of a sub Y fare, or 4 upgrades for a Yx1.5 fare, then youre in the right place and your miles are worth a few thousand dollars. If not as you've found out they're worth circa 800, either way it seems a bit off to moan