Because your company flies a jet with a Garmin 496, you think it is legal? It's not legal for IFR. Where did you get this idea? WAAS capable doesn't make it IFR approved. There are currently no handheld gps legal for IFR operations. No handheld gps meet TSO standards. They all need an approved installation. Sticking your gps on a windshield won't do it. It is only approved for situational awareness.