I have been operating Toro with the Turboforce decks, 60" decks. I have demoed an Exmark with the Ultracut deck. The biggest difference I noticed was the amount of airflow, thus why another user above mentioned the Toro deck is better on thicker accounts. The reason for this is the discharge is about a time and a half larger then the Exmark, which gives it more airflow. This works great in the Spring, however the Exmark will at times prevent you from having to do double cuts because of the decreased airflow as the Toro deck will throw clippings 10' - 20'
The baffle, honestly when the baffle's first came out, I adjusted it a time or two, but no major difference noticed. I leave it open for maximum air flow at all times, not just on thicker accounts.
My best advice, both are great machines and will do just fine-I say for you find out which dealer is better able to serve you and benefit your business, and choose that one.
Toro here is slightly more expensive than the Exmark, but the service I get from my Toro dealer can not be beat, so that's why I have stuck with him.