As with any clear bra on a dark car, the line will be slightly noticeable up close. However, once you step back a few feet, it blends in nicely with the paint. As for the edges dulling over time, I am unsure. I have had my clear film on my monaco blue e90 for 2 years and have not noticed any wear over time.
If the marks under film are not bubbles, which will disappear, then it sounds like maybe the installer didn't properly clean your car prior to installation-maybe some debris is stuck under the film? Anyway, that's just my .02, hope it helps.
e92 335i: Current
e90 328i: Sold 12/7/2013