I have one that plugs into the wall and that shit does work. It gives you a different high, a better one IMO, I believe a more body high but I haven't smoked it in a while so I don't really remember. Vaporizers are definitely worth it though.
And I don't know about two hits off the portable one, but the one I have if you get it nice and hot and take two good hits you'll be stoneddd for sure.