SLR Focusing Screen
My favorite screen for general use is a grid type. I find changing the screens in my Minolta X-700s more annoying than in my Canon F-1s or Nikon F2 so I keep one X-700 with a grid screen all the time, one X-700 with a plain matte screen all the time and two with the standard screens. In My Canon F-1s I like the L D screen best although I have many other types. In 1984 I had an Nikon E screen from the FE installed in a Konica FT-1. I used the camera for many years and found it very useful for macro work and for work with slower lenses like zooms. That camera now needs work. I later had a Nikon E screen installed in an Autoreflex T2 body. I used that camera earlier this week.
I have grid screens for my Bronica ETR, SQ and GS series cameras. One of my Nikon FE cameras has an E screen in it. I was interested in getting an E screen for my two N2020 bodies but manual focusing with the standard screen is very easy. Several years ago I bought a few different screens, including a grid screen, for a Mamiya NC1000S. I find the standard screens in the Canon EF, Nikkormat FT2 and FT3, Konica Autoreflex T3 and T3N, Pentax K1000 and many other cameras to be adequate for general shooting but not so easy to use for macro work or with slower lenses. For higher magnification macro work, anything more than about 2:1, I prefer a plain matte screen. The grid screen sometimes also aids in composition and in keeping lines straight with wide angles.