I reserved my carriage ride approximately 4 months before my wedding. The staff was friendly and very accommodating, and answered all of my questions before I could even think of what to ask. After my initial call, they invited me down to their stables to see the carriages and horses and made me feel very at ease. Once I had booked with them, I wasn't ever concerned about that part of my wedding plans again.
I was married at First Methodist Church (before the fire) and we reserved the carriage to drive my husband and I from the church to The Peabody. The driver was there promptly on time (or before I'm sure, since she was already waiting outside when we finished the ceremony and photos) and she was great. She actually even doubled back so we could get a few different angles for our photographer.
I highly recommend Carriage Tours of Memphis for a romantic carriage ride to/from your wedding.