Hi
Me and my partner went the 10th - 17th Sept last year. The nightlife was good, not too busy but still good. There was a couple of little bars closed above a few of the bigger ones but nothing that you would miss. With you going the beginning of Sept it will be alot busier so you shouldnt have a problem.
Half way up the strip on teh left hand side is a bar called Liberto's, you have to go in. We always started in this bar. They have a live band on each night. Its a lovely place. Its an open air bar, there is a pond with decking on were the band plays. Some of the chairs are beds with silk sheets on, very posh. Cocktails are yum, there about 8 euros each. Have fun!