I had the pleasure of shopping with RJ this january, and this was among the things that I bought. I was looking for a mask for competition and training, and after using it a couple times I can say that this is indeed one of the better masks I've had. I've used previously an AF one and a Red Dragon one, and while they are perfectly OK masks of their own that improve a lot when using the extra leather covers to protect the back of the head, this Wukusy Armory cobra mask functions more like a proper helmet and is comparatively lighter than the previous masks I have owned. It also fits me quite well and moves with my head better than the other masks, so it is easier to turn my head a bit to the sides without losing too much peripheral vision.
The inside padding as others have commented helps to lessen the blows received a bit, and what I liked the most was that the geometry of the mask seems to help with the glancing and scalping blows, deflecting them a bit better than the standard mask and avoiding it getting stuck in the cover and jerking your head back, which already happened to me once while training and it is not fun... it happened while wearing this mask for the first time and while the hit did jerk me back a bit, but by no means was like the previous experience and I can confidently say that just for that this was a good acquisition for me and money well spent, after all our own health and safety is priceless, taking into account that we do practice a combat sport.
I would recommend to check carefully when taking your measurement, since I had the fortune of measuring it instore and the Large model fit me perfectly so I have no trouble with it being too loose or too tight.
I would also like to reaffirm the comments of other buyers that the helmet can be a bit hot, but after a while you don't even notice it, and sound does indeed become muffled because it lacks hearing holes, but it is a small inconvenience to avoid a potentially weak spot in the structural integrity of the plastic plate. I would also recommend that you secure the inner forehead poliurethane cushion somehow, because it can fall down and obstruct your vision in the heat of combat.
Overall, this is a very good mask/helmet, light when compared to similar alternatives, very sturdy, and when fit to form, works quite well.