I want to try out IE 8 beta but I suspect when I install it, it will over-write IE7 in the process. Before I go down that road, I thought I'd ask if anyone has done this already? Does it give an option to install w/o messing up IE7? If not, did you find a way around it?
I've never found a good way to install one without affecting the other, but, IE Tester will allow you to test all versions no matter what is installed: http://www.my-debugbar.com/wiki/IETester/HomePage
http://www.my-debugbar.com/wiki/IETester/HomePage