I found Baccano to be a pretty awesome series. It starts off super confusing and nothing's gonna make sense in the first episode or so but as it goes on everything becomes a lot more obvious and Baccano does a great job with revealing everything. Baccano's unconventional storytelling style makes it stand out because without the jumping back and forth between timelines, it's a pretty simple and linear story so that actually is favorable to Baccano and makes watching the entire thing a necessity. It's also one of the very few series that I can say is almost picture perfect with character development for being a short (13 episode) series.
In my personal opinion Durarara!! is better though. Many people prefer Baccano! but Durarara!! was more appealing to me because I found myself more attached to the characters and the setting was more my style. The two are both by the same author and have similar storytelling, but in terms of setting and the like the two are quite different. If you prefer a western story about gangsters and immortality then go for Baccano, while Durarara!! is more modernized with a Japanese setting and a number of weird supernatural elements of its own (Dullahan, cursed sword, etc.). Of course, the best option is to watch both.