I only installed it so Windows would nativly support PNG files.
Avant is an IE shell, so its also handy for that, but I look forward to IE8. Avant is far better than IE7 in every respect, it also kicks the crap out of firefox and Opera as far as base features goes. And something neat, IE exploits actually do hit IE, not Avant, so usually you can be immune as long as you never load up IE, if you do load it up then you get infected. But it's no big deal to avoid using IE, since all IE required sites work in Avant such as windows update.
I'd probably use Chrome if it had two things changed, 1, a descriptive status bar showing everything from links, to security to zoom level to where your browsing (internet, intranet, network, ftp, etc). And if it let you move the tabs to the bottom of the window instead of being at the top like Avant can.