Many thanks for all of your comments.

Maybe I did not make this clear, but by NGD I meant Hilton's National Group Desk or similar central office for groups reservations at Hilton head office.

My choice is between negotiating directly with Hotel's sales department or with NGD at Hilton. I would not go through travel agent or other independent third party.

As I see it, the pros of going through NGD is only that there would be more possibility of offering us, say, lifetime Diamond status for our execs or other Honors-related benefits. Con would be higher daily rate because they charge hotel commission which would be reflected in rate.

Negotiating directly with hotel should mean lower rate, but probably less ability to offer the organizing company (ours) Honors-related mega-points and/or long-term Diamond status.

Do you agree with this analysis? Any other tips or input you have on this is much appreciated.

BTW, I used Hilton in this post because this is Hilton forum, but I am also considering all of the other major brands, which are all represented in the city. Part of the consideration, of course, is the quality of the individual property itself.