I can't imagine owning an A and a 4020 and not being able to afford less than a hundred bucks on informative publications each year...but I guess oil changes cost more than they used to.
It really depends on what sort of information you like and your tastes to make a good decision on which to subscribe. I get both magazines, but I would tend to lean toward GM due to their real world approach (folks who actually work their antiques rather than have museums in which to store them) that fits my preferences in how I enjoy the hobby. Being published monthly is a plus for me as waiting every other month seems like a long time these days (must be the grey winter days).
My 2 cents...