I have the matt version of this case. It is an excellent fit and enhances the look of the phone, so no problems there. The case has a lovely, almost velvety feel to it. Quite unexpected given than carbon fibre is normally known for its solid feel. However, I have two issues with it.
The first is the strength of the top and bottom edge strips. The case is an extremely tight fit and when trying to remove it I broke one of these strips. Once the case was off I realised that I had also fractured the other strip. Shame, but not a great problem as a couple of snips with wire cutters removed them both leaving the corner protection still in place with only a slight reduction in the top/bottom edge protection. My advice to other users would be to push the phone out of the case from the rear, making use of the gap between the strips and the main back cover.
My second issue is more of an observation. It appears to me that I lose some phone signal strength when the case is on. It appears that I lose one bar from the signal indicator. I live in an area where the signal level at my house is rarely at two bars so losing one is not good, and more to the point, fairly easy to notice. Carbon acts as an electrical shield which is probably why the case designers left gaps at the aerial ends. I'm not sure, but removing the two end strips seems to have improved things slightly .... maybe!
In conclusion, this is an excellent case but does need some TLC when removing and most people won't notice the signal issue.