Buffalo is not hurting for safeties right now (including 4th-rounder Ko Simpson, projected just behind Donte among safeties, signed and in camp), so IMO they have the stronger position here (not to mention Buffalo is a small-market NFL team not looking to break the bank, as you can see from the Clements negotiations). Beyond that, I doubt this will be Donte's only contract, and if it is, that $12M check plus a couple-mill more per played-year would set any reasonable person for life.
(Really, I just want one of my absolute favorite Buckeyes of the past few years to get on the field for my favorite team as soon as possible...)