Ha ha this build is awesome! I'd love to give it a try and see what it's like. A couple points though, remember AOE spells only give a percentage of the spell vamp value, so even though you have 5 X 20% spell vamp, you wont be getting 100% life from the damage your shrooms do. And Early game teemo with an amplifying tomb would be VERY squishy, you're better of getting lifesteal frist and building the AP side of the Hextech late game. I would also suggest putting your 9 points in defence to give you survivability, it would be more effective than reducing the time you spend dead.