The messi topic is an interesting one, part of me agree's about the money side being daft and him being too old, not to be brilliant, but rather to warrant the lay out...
On the other hand, what makes it work out is the simple fact that no other direct or indirect rival gets him. This alone is worth half the fee...i mean how would naysayers feel if city passed him up and UTD or Chelski rolled in to pick him up? Or given the champs league anyone else for that matter?
You do wonder how he would fit into a new team/system(however similar) at this point in his career, especially given how he hasn't qiute made the same amount of impact for the national team...Actually though, given his very small frame and reliance on utterly brilliant technique first and foremost, you'd imagine messi will be at the very top for at least another 3-4 years.
I think on balance its too risky not to take the chance if its there.