PSA buy back?
 

Does PSA still buy back cards which are so horribly misgraded as to be embarrassing to be seen in public? I've got one: a 1941 Goudey graded PSA 7 (no q), where it is so far miscut that the team and player names are on top, above the player photo. So, I'm wondering what to do with it, but I thought I recalled something about PSA buying such atrocities back..... anyone know?

You can have them buyback, or
 

You can have them regrade it with the proper grade and make up the difference to you in grading vouchers. I had them regrade 5 cards for downgrading for me, and received $110 in grading vouchers to make up for the difference in value, which was fair value.

Buy Backs
 

I think PSA is getting much more stringent on buying back cards. I bought a PSA 7 Banks rookie a few years ago, noticed it was badly trimmed and PSA bought the card back. Two months ago I got a T3 with a pin hole in a PSA 4. I sent it in for review and they called me stating pin holes were standard for the issue and can grade as high as a 4, which is complete bs.

sure
 

Sure thing, All of my 4's have pinholes :)

How does SGC respond to buy back requests? I have a card I think they made a mistake on. I contacted the seller but agree with him that it's not his mistake and that if SGC mis-graded a card it should be their responsibility to remedy the situation. I paid $300 for the card. I definitely don't want a $300 grading voucher.

Just what I'd want .... Let's give them the opportunity to screw up more grades or worse yet, destroy your collection by allowing the item to feely "float" around the holder. I'd check to see if the grading credit is transferrable and then try to get 50 cents on the dollar for the voucher.