Deanr,
I have the 4 link on mine and have driven it quite hard on the track and it works great. I have also driven the IRS and I like it. If you aren't really going to do any serious stuff either would be great. But I think that I got a little better feel from the IRS as when I turned one way or the other it didn't seem to take quite as much weight off the outer wheel. But for mostly just driving I don't think either has a great advantage. That being said you should now get about 40 answers telling you I am completely wrong.
Ron
