Well... I have a rather silly solution. It's what I've done for about a year:
You know those big white plastic bags withthey give you when you buy larger stuff in the
Store? Well, what I did was whenever I traveled, I just put the laptop inside that bag and put it in the container like that. They never asked me to remove it (and I've been through many airports with this, even in Europe).
However, now I have a messenger back which came with a sleeve and when I put the notebook IN the sleeve in the container, they ask me to remove it.
So, plastic bag yes, protective sleeve - not.
Hmm interesting idea. I still have my big apple bag. Though it might be a hassle carrying that big bag in the airport. It won't fit well into my backpack haha. The invisible shield is too expensive for mee for the full body coverage.