FYI: Delta service to BUF is exclusively 727 service to ATL. Only rarely have I seen a Delta 732 or MD8x. I have not yet seen a Delta 738 here although I have flown 737NG on Continental, American and very recently, a brand new 73G on Southwest(BUF-PHX). I very much enjoy flights on these planes. I have to admit I no longer have alot of interest in flying on 727's. I have flown in these on American, United, Eastern,
Piedmont, Western, Delta, Allegheny & Republic amongst others since my first flight in a jet a/c (a Mohawk BAC111) in 1965(I think). Oddly, I have been on a 767 only twice (US 762's).