Other Browser Protection

Something that is of concern and has been for some time is that not all security programs check for sites when you do a search using example Maxthon or Opera browsers and then warns or blocks access before the site is opened. This also applies to downloads etc. How much would be involved in implementing this full scan protection (all your HTTP traffic)? I realize that some protect after a file is downloaded and then execution is attempted but I'm not confident this works each time. I wish Norton would have full coverage for all browsers beyond IE, Chrome and Firefox.