I recently took of my 190E's non-full size one to replace with a full-sizer, and drove it for a while without it on. The engine was a lot noisier without it, emitting generally unpleasant whineing and grinding sounds.
All I can say if you are removing it for a weight/speed advantage is that you are absolutely CRAZY and I may have to go ahead and kill myself

. My brand new full size pad weighed much much less than a big lunch, I thought it would be a dense, heavy material but it seems dense and lightweight.
And as I've never noticed a speed difference when driving after eating, I'd say definitely leave it on there.
later