Summary: The original focusing screen came loose and was damaged. I chose this type to assist lining up my photographs and horizons.The screen comes as a kit with a tool to fit it and clear printed instructions provided.Fitting is not difficult but must be done carefully and in a very clean dust/draught free environment. It also pays to clean the camera inside first to insure no dust there before fitting the new screen as the slightest mark will show.
Summary: Easy to install, comes with tweezers to ease with the installation and to avoid touching. I have never been good at getting a level horizon, this product solves the issue. Provides light non distracting grid lines that enables you never to be able to get horizontal and vertical lines wrong.
Pros: Cannot Do Without, Easy To Use, Improves Product Function
Summary: Its better than the standard screen in the 6D.Just be careful not to get any dust specs on it when putting it in the cam. Is a little tricky but has clear instructions a monkey could follow. Helps composure.
Summary: I bought this to help when using my Canon TS-E 24 F/3.5L Mk II, or my TS-E 45. Without it I quickly realised that holding the camera accurately vertical was a problem, and I didn't want to have to use a tripod for all of my shots - far too restricting.It was easy to istall, and the fine grid lines are easy to see in the viewfinder, as well as the focus points. I expect I'll leave it installed.
Summary: Definitely improves both composition and levelling of your images. The 7D has an electronic version of the grid viewfinder, but the 5D Mk2 does not, so this accessory is really helpful in aligning objects in frame. Great for levelling a landscape (better than a spirit level on occasions) and architectural shots. I found it invaluable for setting up studio shots, where pin-point alignment is crucial.
Summary: I've never been very good at getting the horizons straight / verticals vertical in the frame. This is an excellent aide. Simple to fit. I can't think of any reason to ever take it out and revert to the standard supplied focus screen.
Pros: Easy To Use, Improves Product Function, Lightweight
Summary: despite having a good eye for what is level or not i have found myself having difficulty in getting my images level in camera and the use of this screen has made a huge difference saving me a lot of time in correcting misaligned shots that i have taken.it ought to be a standard fitting.