Even the genki fall into despair sometimes.
Baccano! ran for an unconventional 16 episodes. Through the equivalent number of Durarara!! episodes, I give Baccano! the clear edge with the deciding factor being its superior characters. (As both shows have large ensemble casts, I'll address relatively few of them herein.)
Besides, Baccano! has much snappier dressers than Durarara!!
This is not to say the characters in Durarara!! are lousy, just that I don't care about any of them. I do enjoy the crazy antics of stalker girl extraordinaire Mika (seriously, she's Cocoa Puffs), but that's about it. I thought I'd like Celty more, but as I mentioned earlier, I don't like how she's so easily flustered. She's also not very smart, but I guess that's not a nice thing to say about a girl who does not have any brains.
Takashi tries to sweet talk Anri.
Okay, I do actively dislike Mikado, Masaomi, and Anri. Even Mikado's big moment suffered from two huge Angel Beats!-level flaws that pretty much sapped any coolness out of the triumph. He's lucky it worked out, I guess. Actually, Anri is a special case. Through 15 episodes, Anri's biggest problem was a complete lack of charisma (unless you measure charisma in cup sizes). I was left hoping she'd give in to her predatory teacher's obvious efforts at grooming her for sex. Really, what did she have to lose? But after episode 16 you have to be curious what else she has hidden under her clothes. Anri's school must get its uniforms from the same company as Iriya's. [P.S. Spoilers.]
These two have the dirtiest pillow talk.
Baccano! is superior to Durarara!! because it has Isaac and TOP FUEL GENKI Miria. [Yes, more spoilers, I know.] Despite Miria's horrifying voice, every scene those two are in is pure gold. Baccano! also has Chane doing wonders as a girl who doesn't talk. Durarara!! also has a girl who doesn't talk, but it's just not the same. Chane far surpasses Celty even if Chane probably spends most of her free time honing her knife fighting abilities instead of chatting idling on a computer. If she's going to spend so much time screwing off on her computer, Celty should at least check eBay once in a while for her head. Make a token effort, sweetie.