Vantaggi
Arkadium is a special, unique company. I've seen more than a few, and these guys are unlike any other. The company's been around for well over a decade and the culture has evolved in a very specific direction: super-positive people, high achievers who are also authentically nice.
The office is clean, modern and beautiful. Subtle perks are everywhere: exceptionally good coffee (seriously - it makes a difference), fun companywide activities in and out of the office, arcade-style video game machine, periodic free meals, massages, etc.
For me Arkadium was a place where, irrespective of title, there was always the opportunity to grab more responsibility if you could handle it. They're too established to be considered a startup at this point, but the freedom of "if you see something broken, raise your hand and/or fix it" (which is a kind of startup-y ethos) is still very much present.
Svantaggi
The above-described warmth and camaraderie are nourishing and awesome if you're into that sort of thing, and I 100% was (which is why I had a great experience at Arkadium). Reading through some of these other reviews it seems like for some people that vibe is..decidedly not for them.
So to prospective applicants I'd say this: pay attention during the interview process to the personalities you encounter, the tone of the place, the way people express their ideas. If it feels refreshing and exciting, you're in luck, because that culture is real, and pervades Arkadium. If it feels like it's not for you, maybe it's not for you.