Personally I haven't had any concerns about the longevity or durability of the wraps, and that's living in a climate with 20 degree (F) winter temps through to 100 degree summer temps.
Here are a couple of pics of a vinyl wrap as applied to my last tarmac rally car in 2008:
And here's the same car in 2012 when the wrap was about to be removed:
Please note I'm not an installer or reseller of vinyl products so I can't speak beyond my own personal experience, but I've never had any issues with the quality of the wraps on my personal cars, even after a few years of use.
We keep the company cars wrapped for around 7 years before they're stripped and traded and again I haven't seen wear and tear on the vinyl that's too much different from the wear and tear you'd get on regular paintwork over the same period.