Just read it. And it's gorgeous.
I think that for people who love 2000AD (so basically anyone reading this), this is a no-brainer. It's the beginning of a straight forward, though compelling, sci-fi adventure story, but Graham resists the urge to fill the book with exposition. John Prophet's current journey is what's important here, and so we must be satisfied with following that. The rest will come later, but thankfully Graham gives us just enough to make us trust him that more info is forthcoming.
The art is quite beautiful. There's some Moebius, some Guy Davis, and Simon Roy shows that the talent he showed in Jan's Atomic Heart was just the tip of the iceberg.
In short, I kind of loved this book. I'm a little stunned that we now have 3 (along with Casanova, and Spaceman) top notch North American sci-fi comics on the market.