No. I'm just going from what I read on a cereal box.
Yes. I've heard both. And both are excellent cans. But IMHO not even remotely close in sound. The senn is lush, warm, intimate and detailed. The akg is much more analytical, dry, cold in its presentation. But, the width of soundstage and giving you every micro detail is the akg strong point. The bass is there, but it's cold and dry, which makes it sound bass lite. Essentially you have to find an amp that colors the akg into what you want.
Having said all that, I love the akg. But it is in no way similar to the senn.