The Digidesign POW-R is a dithering plug-in that comes with Pro Tools. POW-R dithering can be seen all over the place in different plug-ins, and Digidesign has their version that comes free with all versions of Pro Tools. I didn't have any compatibility issues considering that it is made for Pro Tools by Digidesign, who is now just going under the Avid name. You don't need to do anything to install this dither plug-in as it will do so when you install Pro Tools. The interface of the software is very simple, with options to set your bit rate and your type of noise shaping, which I believe there are three settings for. A manual is absolutely unnecessary for this plug-in.
I'm running the Digidesign POW-R dither plug-in in Pro Tools 8 that I run on a Mac Book Pro that has a 2.2 Ghz Intel Core 2 Duo processor and 4 GB of RAM. I run Pro Tools with a Digi 002R audio interface, and I can't say that I've ever had a problem at all running this. I can't imagine that any user out there will have a problem running, as if you're running Pro Tools already you shouldn't have a problem at all. Also keep in mind that you really only need to have one of these open at a time within a single session.
Digidesign's POW-R dithering plug-in is generally the plug-in that I will use when it comes to dither. I find that it gets the job done just fine, as will any plug-in with POW-R dithering. It's just nice to have a free dithering plug-in that comes with Pro Tools, as it is necessary to have and isn't something that I would want to spend any money on. If you've got Pro Tools and you need dithering, look no further than the POW-R plug-in for Pro Tools.