giftcards and transferring miles ever worth it?
 

I just used 56k old miles from my wife's account on skymiles marketplace to get giftcards for 8k a piece for a $50 giftcard. After I did this, I looked at my account and see that they are only 5k a piece for the same $50 giftcards. Is this because of my platinum status or my gold delta amex? If it is the amex, it is a joint account, so shouldn't it have shown as 5k for her as well? I figured we'd never really use the miles in her account for any travel since she'll never really get a lot of them, so giftcards seemed like a reasonable thing to get.

Another question-- is it ever really worth transfering miles? If I read it right, it is $0.01/mile + transaction fee of $30 to transfer miles. So for my wife's 56k miles it would have cost me $590 to transfer them to my account?! Even with the 50% bonus and having me pay 5k instead of 8k miles for giftcards from my account, I would have lost money by transferring them.