E load rated tires have very stiff sidewalls and you'll take a pretty big hit to ride quality. The extra thick sidewalls do provide a extra safeguard against punctures while rock crawling but most modern AT/MT/RT tires have reinforced sidewalls regardless of load rating.
^2nd this. In general, it seems like Kings have a longer life cycle than Icons but King doesn't have the best reputation in our climate. They have issues with rust and pitting on the piston rods unless you are doing a ton of preventative maintenance/cleaning/coating.
Don't buy stiffer/heavier...