My feeling on this is that there are three players that are relatively similar in terms of ability.
Parker and NRC have each had the odd stunning season and since gone off the boil, albeit in NRC's case there have been mitigating circumstances, having hate male from your own fans will piss you off, don't care who you are.
Parker had one sensational season at Charlton, went to Chelsea did **** all, then to Newcastle and didn't do much there either. He's seen the dollar signs and bright lights of London at West Ham - they're welcome to him.
Barton is a an absolute lunatic, a good player yes and would be a bit cheaper, but we no longer have to worry about the odd two million quid here or there.
Getting NRC away from London and in with MON will IMO be the making of him, I think he could be excellent for us.