The first book is kind of rough, Serge is more of a straight up psycho than a lovable and infectious one. But Dorsey really found out how to write the character and the world(it's Florida, but it's FLORIDA!) after that.
I think I'm two books behind, last I read was The Riptide Ultra-Glide. The quality from book to book can vary, but they are almost always entertaining and very funny. It's not really very similar, but the books I most compare them to in my head are the Discworld books. Everyone is crazy in some amusing way or other, completely improbable shit is the norm, and comedy rules the day.
Got a big kick out of the political one, Orange Crush. And while Gator-A-Go-Go wasn't the best it featured Coleman at Spring Break a ton, which was outstanding.
I'm a big fan of the series.