I have run Steinberg Wavelab 4 on a few different machines, but mostly have used it on a PC lap top - a Hewlett Packard Pavilion dv8000 that has a 3.0 GHz processor and 2 GB of RAM. I have used it on a few other PCs as well, all without any issues. Since this is a mastering and restoration piece of software, I don't need to run a lot of tracks at once with this. However, I am able to run as many plug-ins and effects processors as I'd like when using this software. It has always run smoothly on all of the machines that I have used this with.
I've been using the Steinberg Wavelab 4 for the last three or four years. It is an easy program to use, with a lot of power and capabilities. I use it mostly for mastering or for editing stereo audio files, and these types of applications are really what this program is made to do - and it does it well. Steinberg makes some powerful pieces of software that won't cost to much, which makes them a great option for home studio owners. Wavelab 4 won't cost too much when compared to some other mastering softwares. I highly recommend Steinberg Wavelab 4 for mastering and digital audio restoration.