I no longer have a compatible system for the Silverspike TapeIt 1 plug-in, but when I did run it it was in Cubase SX. I ran it on a Hewlett Packard Pavilion dv8000 lap top with a 3.0 Ghz processor and 2 GB of RAM. The plug-in takes up only a small amount of processing power, and being that you'll probably only be running one of them at a time anyway, performance shouldn't be an issue at all with this plug-in.
Silverspike's TapeIt 1 plug-in is definitely a cool idea for easy exporting, but I'm not sure that it's all that necessary. Something like this should be available in most DAW's, but I definitely do see where the convenience comes in as you can easily pull from any audio file and create a new one with it. It won't change the quality of the file in any way as well. So while I'm not sure I'd recommend this to everyone, I would at least encourage you to read up on it a bit more to see if it's something that you might find useful. I can't say that I'm missing it now that I don't run it, but I probably would still have it if I still had a compatible system...