Thanks so much for all the compliments everyone! Here are a few more that I didn't include in the original post that you might find interesting
Very nice, Savy. Glad to see that 91-S cross. Wish I had held onto it. That 81-S is super nice for 66! Very pretty.
It depends on the toning. I'd never seen toning like this and figured it couldn't hurt to spend $30 on grading/imaging it. But on a common date Merc with average toning, I'd guess it wouldn't be worth it.