Hi.
Just now saw your post
My experience is that the latest T.I. Burr Brown opamp chips are very close in performance to the discrete SX52B opamp. The main difference is increased noise in the discrete opamp.
If you are using multiples, you can save a substantial sum by sticking with the chips, such as OPA1642 and OPA1656.
I hope this helps anyone with a similar question.
-Chas