I have stayed in the towers on 3 occasions and an exterior on 1 occasion (all 3 times was upgraded to the tower free!). As far as the rooms, both were fine to me. The tower rooms have more of a view. My exterior room faced the parking lot and was on the third floor but I did not wake up at night from any noise. You will find some people complain of noise from the parking lot in the exterior rooms.
It's a great location to DTD.
My mom is a smoker so when we stayed in the towers she had to go downstairs to smoke because the tower room does not have a balcony. Actually, I did see her once smoking on the exterior stairs but that is probably frowned upon. In the exterior room I did walk out once and a guy two doors down was standing there smoking. It wasn't enough to bother me since I grew up in a family of smokers (but DH and I do not smoke).