Unexpectedly good, waterproof, doesn't let water in, blocks cold air.
I would prefer it to be one piece under the palms instead of mesh so it cuts off the air from there as well.
You need gloves on your hands.
The part that hugs the handles is loose, so it can fit a thick glove to press the flash.

Sometimes if I accidentally lift it or carry something, my shoes stick out from underneath, so they either get a bit wet or cold air comes through.
Not that it has a problem as it is now, but it would be better if it had another 10 centimeters in length so I could step on it with my feet to lock it in place so nothing ever gets through.

It takes a little getting used to putting the key in the ignition and starting the bike before sitting down because after that you can't see the hole :p unless you're an easy rider and your key goes in automatically.

One of the biggest advantages is that it's ugly, so even gypsies don't steal it.
I keep it outside permanently, and no one has shown any interest yet...

Although it could have improvements, it generally works just fine, 5 stars for the €8 and the anti-theft mechanism!

EDIT 3 min: it's torn with a seam, so it cuts and unravels easily. If you don't have a sewing machine, don't bother getting it at all.