Statistically, he might be THE best tight end in the league.
And in terms of his value to the offense, he might be the best, period.
I saw a graph earlier about Dalton's numbers passing between the hashes and how he hasn't thrown a pick in the middle of the field yet, compared to 11 last season. The entire reason for that is Eifert, IMO. He catches balls down the seam, or he clears out the defenders and let's Green/Sanu/Jones find space in the middle. It's amazing the difference he makes, because Cincy couldn't do that last year.