I have searched the archives of this forum and others, and still have some unanswered questions. I use a Canon 5D for most of my shooting, and a 20D when I need the longer reach. I usually use manual focus (which is obviously much easier on the 5D than the 20D because of the relative viewfinder brightness). However, I still miss the exact focus point on occasion, using the standard screen. I have researched several alternative viewfinder screens, and would like to hear from people who have actually used them! Since I do a lot of macro photography, I often stop down the lens for more DOF. I have been told that manual focus is not feasible with the alternative viewfinder screens because they darken down too much to be usable. I understand that split prism viewfinder screens interfere with spot focusing - I can live with that if it is the only drawback. I have never had a problem manual focusing with my old Canon A-1 -- I sure would like something like that for my 5D! So, if any of you have used alternative viewfinder screens with a full frame DSLR, please let me know how they worked.