No, I absolutely would not do it. I'm happy to enjoy our space exploration vicariously. I'm going to stay with my feet firmly planted on the ground as often as possible. I don't even like being in airplanes.
But good luck to the four. I hope they have the psychological fortitude to not only make it through the claustrophobic nature of the experiment, but the ability to stand each other's company for that long. Of course, it will not have anywhere near the challenges of real Martian exploration, but it will be an interesting experiment nonetheless.