I think at the price point, for a transport and storage bag, it might work well for some. I might even consider it for occasional trips where I want to charge in the hotel room, etc, because with the long handles it could perhaps buy enough time to drag the hot bag out onto the step or balcony, etc. The bags all have similar weaknesses/problems with charging, and it's not likely to fully contain a large lithium cooking off. Many bags do perform reasonably well for smaller batteries though if you are just doing R/C toys or such.
For the large ebike batteries, a metal tool box or ammo can is generally the better bet and quite cost effective vs the few bags that are properly designed for the task. Regardless of what you use, they should always be considered a means of damage/flame 'reduction', and you still have to use care in the setting you are charging in. You cannot completely contain the expanding gases, and if you try you will just make a bomb. It's about releasing the gas in a controlled way that contains the flame as much as possible. The last video tomjasz linked is a good example.
A superheated can on a shelf can still set combustibles around it on fire when it vents suddenly at 1000+ degrees, and the fumes are very toxic in a confined space.
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