I disagree with MiamiAl, I too have been dealing with them for over a decade. Even if you think Lou's has bad customer service, I guarantee you will not find a better gun shop in miami. They have the best prices, and have a pretty good inventory on stock. If they don't have what you are looking for, they will order it for you.
As far as warranties go, you should deal with the manufacturer. I know that many people are accustomed with their local store to deal with warranty issues, but the reality today is that you must deal with the manufacturer, which is why I make sure to buy products made by companies that are reputable in terms of quality and service.
The only other gun shop that I've found to be decent is Florida Armory, I tend to think they are worse in every respect... and Ace's would be third in the Miami area.