Must admit in some ways its a nice piece of software but it does seem to render a few sites slowly as Bifta has said, I use myie2 since it has tabbed browsing which comes in handy for opening multiple sites at once.
Im using firefox at the moment to post this but I don't think I will be setting it as my default broswer just yet
Especially since I've only just talked my significant other into using MYIE2 instead of Internet Explorer.