The financial piece is obvious... it is depending almost wholly on grassroots and media based funding, which is of course tenuous at best. Once a team arrived on Mars I feel they would be fine, because at that point, the groundswell of support that was started by the Apollo missions would take over. It's getting there that would be the problem.
There would be no rescue, if things went wrong. THAT technology simply doesn't exist yet, which is why this is being pitched as a one way trip. If I did sign up, and managed to make it there, I would know that I would probably die on Mars, the only question would be if it was sooner than later.
But lay your idea of the technical issues on me. Why is this not technologically viable, if one assumes a one way trip?