If you are going to buy a Mind MGMT page, I'd do it soon, the primary market is starting to dry up with most of the "a list" pages getting snagged quickly. And I am sure the secondary market will have a big mark up, if they even ever do go on sale.
So tough... OA or SA/BA/Modern Key
I've had this debate with myself and I vacillate. If I were not on my phone right now, I could write you a thesis on my thoughts. Short answer is: it depends
I am pretty bias as an art collector. But my logic is Matt Knidt will never draw another copy of issue 1 page 4. OA is truly 1 of a kind....
And buying art from the artist directly (or their rep) truly supports them directly.
And for something like this series... you can get a NICE page for $300, or a cover for $800ish....
Considering the cost to get key issues, that's fairly nominal. but it's also not apples to apples, because a page from a key issue is going to start in the 15-20k range these days.
My interest lie more in collecting OA than keys and my statement was generalized & not a reflection of Matt's work (I just happen to be expressing an opinion in the MM thread). BUT, if I had to choose - for example - between spending 3k on a decent AF15 or a walking dead cover, I'll go with the AF15.