This is a plugin that comes free with Pro Tools (hence, I did not include the price with the review). It is a digital reverb. There aren't any compatibility issues with this plug in, it's installed automatically with Pro Tools, so assuming your Pro Tools installation and setup go smoothly, you'll be in good shape with this plug-in. The controls include mix level, input level, diffusion, decay, pre-delay, high cut, and a low pass filter. There are also different settings for different types of reverb, which go by the standard names of church, hall, room, etc. I've never looked at a manual for this plug-in, though I doubt anyone who has experience with any plug-in should have a hard time, in fact I doubt anyone would.
The software has never given me any problems with it's performance. Sometimes, when I am in the middle of playback, and I try to insert the plug-in on a given track, I get some hesitation from the system, which can be frustrating if you are trying to mix. This tends to happen with all plug-ins though, so to say that this one in particular is a problem would be misleading. Obviously running this plug-in on every track is going to be a difficult thing for Pro-Tools to do, so I would have to insist that you don't do that.
I think that the sounds of this reverb are OK for some projects, but not always perfect. Obviously, buying a good reverb plug-in will definitely be better than the one that comes standard with Pro Tools. However, if you are doing a small project at home, this would most likely cover your basic needs. I think that the bigger your setup, the more necessary it is to buy more plug-ins. If you are using an M-box and an SM57 almost exclusively, you really won't have much need for a better reverb, but if you own a professional studio, I'd say that you really need something better than this.
Digidesign's D-Verb is a reverb plug-in that comes free with all Pro Tools software. I've run it both in Pro Tools LE 7 and 8. I believe that the plug-in can be found in some of the earlier versions of Pro Tools, but I don't know this for sure since the earliest version that I've run is 7. The plug-in has remained unchanged as far as I can tell between these two versions however. You don't need to take any action to install the plug-in once Pro Tools is all set, as it installs all of the DigiRack plug-ins during the initial process of installing Pro Tools. The interface is really straight ahead, as I'm sure they were trying to cater to new users with their free plug-ins, or at least wanted to make them as user friendly as possible. The parameters that it has to work with include sliders for mix level, input level, diffusion, decay, pre-delay, high cut, and a low pass filter. It also has a variety of algorithms to choose between different types of reverbs, as well as three different room size options. Some of the algorithms include hall, church, plate, and room reverbs. I don't think that there is a manual for this plug-in, unless they say something about it in the Pro Tools manual.
I'm currently running the Digidesign D-Verb plug-in and Pro Tools LE 8 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 8 with a Digi 002R audio interface or a Digidesign Micro Box if I'm on the go. I've also run the plug-in a small amount on a Pro Tools HD system. However, no matter what system I'm running this plug-in on, it doesn't seem to take up much processing power at all. I should mention that when I use it, I do so on an auxiliary track and I bus individual audio tracks to it to save processing power anyway, which is what I do with all reverb and delay plug-ins to a degree. Either way, you should be able to run D-Verb smoothly if you're able to run Pro Tools well.
Digidesign's D-Verb is their original reverb plug-in, and from what I can tell, is one that hasn't seen too many changes in make up over the years. It's always been easy to use, and while the sound quality isn't up there with TL Space or anything like that, it does have a very respectable sound that is capable of getting a wide palette of different reverb sounds. While I'd personally recommend adding TL Space Convolution Reverb to your Pro Tools suite, D-Verb is more than adequate for those just getting started.