I did have high hopes for the film given that Michael Mann was at the helm and not only had I enjoyed his original TV creation but I had loved a number of his recent films including "Heat" and "Collateral" (also featuring Jamie Foxx). Unfortunately, "Miami Vice" holds none of the suspense or excitement of these other two projects.
The drug cartel background story is a rehash of not only a prior Miami Vice TV episode but a retread of numerous other films/TV shows over the past twenty years. There is nothing here that hasn't been done over and over and over before. The plot would have been better off sticking with the story set up in the first few minutes of the film, one of human trafficking, instead of just using that as way to introduce all the key players.
The casting here is all wrong as well...mostly in the case of Colin Farrell and Gong Li, but also in the case of Jamie Foxx. Farrell and Li both mumble their way through the film talking like they have marbles in their mouth. I expect to have a bit of a difficult time understanding thick Scottish accents in a film like "Trainspotting" but I don't expect to miss half the dialogue in a film that is ostensibly about American police officers. Li also may be an attraction in China but here she comes off stilted, unattractive and borderline crippled/abused/deformed. Foxx is his usual stiff self, monotone and with little expression but given that Tubbs was similar in the TV show, this isn't as big a deal. And who thought the moustache and mullet was a good idea for Farrell's Crockett character?? OK, I understand you are looking to differentiate him from the TV Crockett but a mullet?? Really??
Action wise, Mann has done a much better job in Heat and other films and again, there is nothing new here. I do appreciate that Mann's gunfire sounds like real gunfire and not some cartoon version thereof but that is a small checkmark on a list of empty boxes.
All in all it just feels like Mann and the cast are going through the motions in order to collect a paycheck and fullfill a contract. Watch "Heat" or "Collateral" again instead of this bad idea done badly, you'll be much better off...