I am currently running Sonnox Oxford Reverb on a Mac Book Pro that has a 2.2 Ghz Intel Core 2 Duo processor and 4 GB of RAM. I am running the plug-in strictly in Pro Tools LE 7.4 that runs with a Digi 002R or a Digidesign Micro Box, depending on where I am working from. I can't say that I've had too many issues running the plug-in within this configuration as it has always run pretty smoothly for me. However, it is important to note that I use the plug-in on auxiliary channels to save processing power, which is what I do with all reverbs and delays. As long as you have a system that you are currently able to run some plug-ins on well, I don't think that this reverb plug-in will present you will any performance problems.
Sonnox Oxford Reverb is a very versatile reverb plug-in, more so than most of them out there. It has a very clean sound and is capable of emulating all sorts of types of reverbs. I love having so many parameters to work with because it gives me complete control over my sound and makes it possible to get a wide array of different reverb tones. The price of the plug-in is more expensive than most, but for professionals looking for a go to reverb plug-in, the price is reasonable. If you are in the market for a high quality reverb plug-in I would definitely recommend checking out this plug-in along with a variety of other ones, including TL Space, Softube Spring Reverb, and Digidesign's reverbs.