yeah some pages wont work n firefox but since firefox is fair to us, they allow you to open ie and the website u cant view from inside firefox. also another major avantage other than security, is being able to download very large files faster and without crashing. IE crashes when u transfer large files. another thing you might notice is when u are downloading stuff using ie and u close the website u downloading from, 50% of the time the download file will cancel/failed and u also dont have the choice of "resume or retry" a file n ie.