1) Can the Logitech Ultrathin Keybord adequately accomodate an iPad 3 fitted with a "back shell" type case? 2) Is there sufficient magnet stength on the Logitech Ultrathin Keyboard to hold and secure the iPad along with a "back shell" type case? 3) Which specific brand/model iPad "back shell" type case(s) have been confirmed to work on the Logitech Ultrathin? Which one is the lightest and thinnest? 4) Which of these cases allow you to "freely remove" the smart cover without having to first remove the back shell case? Thanks.