First Impressions: Visuals / Audio are standard. The mystery is intriguing, and the format is actually reminiscent of Lost (yes, the US TV drama). I'll watch because anime like these usually have a nice cerebral element to them if nothing else.
Similar to: (but worse than) Gantz - both main characters are naturals at their respective games, but start off as cocky, reluctant wimps. But the setup puts it closer to (and worse than) Mirai Nikki, another survival game anime.