At this stage of his career, unless it was Cleveland, St. Louis, Washington, or Oakland offering their 1st rounder, you do not trade Martellus Bennett. Behind Jason Witten, the only legitimate TE we have is Bennett. Phillips is great, but as a blocker, not a down-field potential pass-catcher, and he certainly wouldn't have made that first down catch yesterday.
Unbelievable that the same people that were whining about lack of depth would trade away potential Pro Bowl (he's got potential, okay?) caliber depth for a 1st round pick with a team that's currently at the top of their division?
Like slomoxn said just above me, good tight ends that are complete (pass catching and blocking) certainly are not dime a dozen. Bennett's got a ways to go in the blocking game, but the upside is worth much more than a Cinci 1st round pick in my humblest of opinions.