Just want to give a WORD OF CAUTION to those who are planning on installing this, or any other, focusing screen. I followed the same steps, more or less, described in this thread when I got my S-type screen from focusingscreen.com. I was almost finished, had the new screen in its tray and was about to snap it back into place, when I noticed a large spec of dust. So, I took it back out and grabbed my Giotto Q-ball rocket blower to blow the dust off. As it turns out, that was a REALLY BAD IDEA! The Giotto blew a bunch of rubber gunk onto the focusing screen that I have yet to be able to get completely off. I went from having one fairly innocent little dust spec to a having many black specs of gunk all over the screen. I could have probably avoided this disaster if I'd pre-blown the Giotto several times to get any residue or whatever junk inside of it blown out first but, unfortunately, I didn't think to do that. Now you know though so, DON'T MAKE THE SAME MISTAKE!
To get the screen somewhat clean, I more or less followed the steps shared by JohnBee in post #20 on this
thread. That improved my situation from dire to liveable but I still have three prominent black specs on my screen along with a barely noticeable dried water stain. During the first attempt at the cleaning process, I just about had a heart attack when the focusing screen slipped out of my grip while blow drying and flew to the filthy ground. Luckily, that didn't ruin it. I expect that at some point I'll get the screen completely clean but I'm not sure when or what it'll take. For now, I'm living with it being a little dirty.
The S-type screen is a big improvement and as far as I'm concerned it is a must have if you are using any of the FA Limiteds or similar fast lenses. I wish I would have gotten the focusing screen sooner, it certainly would've saved a few shots, but I also wish that the installation process, and cleaning process for that matter, weren't so hazard prone. Accurate manual focusing is now actually possible for me, and quite enjoyable, with my FA 31 and 77. So, by all means, get one of these great S-type focusing screens, but be VERY CAREFUL installing it.