We did the Grand I during our wedding-
But we also had the carriage. Since we spent so much on the carriage, we did our grand exit in the carriage and it took us to the Grand Floridian Marina, where we boarded the Grand I and it drove us over to our reception at the Contemporary.
Of course you can do any version of this you want.
If you aren't doing the carriage, you would probably do a staged exit, a quick turnaround in the Grand, and come back for photos. Once you were done, you may be able to use the Grand for a quick trip, depending on where your reception is, it could take you there.
It just really depends. You can get the grand for 1 hour around $400 (dec. 05 pricing). It takes a good 30 minutes to get from the GF to the contemp.
The Grand cannot go fast on the lake because it flips the little rental boats over.
Brittany