Installed Katzeye focus screen on 7D
 

As I accumulate more manual lenses for the 7D (and t2i) I find manual focusing very difficult. I've been reading about Katzeye focusing screens that function like the older SLR's split prisms. I ordered one last weekend opting for the more expensive "Optibrite" treatment. The installation was a breeze but perhaps a little scary for someone that isn't mechanically inclined on a mini-scale. It took me about 15 minutes time and I believe I could do it in 5 if needed again. The instructions were excellent, but one detail I think they could have added was to use a magnetic screwdriver to hold onto the tine screws (fortunately mine was). The screen is very brite, and the autofocus seems to work fine. Several other reviewers commented that the split screen is useful for calibrating the AF. So far my tests seem to show the AF and manual overlap exactly, so not an issue on my copy.

Looking forward to taking the lenses out the next few days and giving this improvement a workout.

I always liked a split-focus screen, bu t don't you lose the optical viewfinder when shooting video?

On the 7D and t2i the mirror flips up to expose the sensor when taking video. You can use the viewfinder before starting video if using Quick-Focus, but once you start, the viewfinder goes dark and everything is via the LCD screen.