Would metro PCS and iPhone work well?

I'm buying an iPhone 4S and I'm apparently (my parents) wanna switch to metro PCS, in fact they ARE GOING to switch by the end of the year. I've heard that metro doesn't have a very good service, but a couple of other people have told me that it depends on the phone I have, so… Would the service of metro work well with the iPhone? (By service I mean if I would get signal pretty much everywhere and browse fast to the Internet)

Look http://m.cnet.com/news/why-metropcs-doesnt-carry-the-iphone-yet/57497471

http://www.google.de/...nd+iphone5