I use the GS Air-M and MS exclusively and I assume the GS Air is just a different version than mine because it looks just like them. $4.80 is a very god price.
What do I like about them. Everything. I have never had one leak & that is a biggie for me. The coils last me two weeks (vape 50/50 juice at 3.3v, 3-4 mls/day). I think they are elegant looking. The AFC works great. The only thing I would change would be to make the juice hole a bit bigger but after a while you get used to it.
If you plan to try one dont buy it from China. Their AFC dont work well. They are so loose they move on their own. I superglued mine in place and that worked.
As far as recoiling
@Cheechako has a video demonstrating it if you want to try it. He told me it's a steep learning curve though. He's right. I've done it a few times but am still in practice mode

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