Haven't needed to yet. But I would guess it would work better if there was water instead of air in the bottom.
Yes, but you probably don't want to as kitchen piping is a lot smaller and easier to break. I have plunged a sink and broke the trap in doing so.
Ahh. Right here. I've used this exact type on my bathroom sink a couple times. Please save yourself the clean up and put your finger over the overflow before pussing water down or you'll get the mirror wet. Depending on your faucet you may have to collapse it a bit first. There will still be plenty of pressure left in the bellows.
Yes the handle is friendly and easy to plunge
I'd use bellows plunger to try since the push is much stronger than the regular toilet plunger.
My understanding is that it is specifically made for toilets.
If it works on a Kitchen Sink, I am sure it will work on a toilet