When i was looking for crashbar bags i also noticed those but i decided not to get them.
I was afraid that when i put something in it and i drop the bike that the crashbars became useless as the filled bags can damage the plastic.
First i had crashbar bags from Lomo but they weren't crashproof and now i have made a harness on the back of 2 Aux Pox from Mosko Moto.
Here i have the Lomo, not bad considering the price. Just don't go offroad with them on tracks with a high risk of falling.

And this is my Mosko Moto version.
