Installing the McDSP DE555 was a quick and easy process as I experienced no issues at all. I had no compatibility issues at all with my configuration and the interface of the plug-in couldn't be any easier to follow. The plug-in contains three sections - one of key filter, one of de-esser and one for output. The key filter section has parameters for frequency and focus, as well as buttons for choosing type and bypass. The de-esser section has knobs for range, ratio, and release and the output section simply has a knob for level. Within the McDSP DE555 also lies two graphs that show both frequency response and dynamics. I don't have the manual for the McDSP DE555, but it is easy to install and use so you shouldn't really need one.
I am currently running the McDSP DE555 on a Mac Book Pro that has a 2.2 Ghz Intel Core 2 Duo processor and 4 GB of RAM. I run the plug-in in Pro Tools LE 7.4 that runs off of a Digi 002R audio interface. With the configuration I've never had any issues at all running this plug-in, and I am able to run a few of them at once if I so please to, but I usually don't use this all that often and when I do I will only use one or two at a time. However, it is good to know that you could run a bunch at once if you wanted to.
I've been using the McDSP DE555 for about a year and I've found it to be one of the better sounding de-esser plug-ins that I have used. It has a good amount of parameters which makes it a very versatile plug-in as far as de-essers go. It is very easy to follow and use, while the graphs are convenient and come in handy. The price of the McDSP DE555 is relatively cheap as far as plug-ins go and it would probably be the first de-esser I would recommend for home studio owners looking for a cheap option that still sounds great. Overall, the McDSP DE555 is a great de-esser that has the capabilities far beyond that of de-esser plug-ins.