I received the Rockbros wind jacket today. One week to ship from from China isn't too bad at all. As I mentioned, I ordered the 3XL size, hoping it would be the right fit. The good news is that it appears to be comparable to an XL (maybe a tad larger) here in the US. At 6' 3", 190 lbs, it appears to be the perfect size to allow the use of the Montbell UL Down or other insulating jacket underneath it. Sleeve length is just right for me with a little to spare. Here is a pic with the original Faux-dini in XXL for comparison:
It weighs 4.0 oz on my scale, compared to the 2.7 oz for the XXL Faux-dini. I was hoping for a little closer to 3.5 oz, but it is a much larger jacket so it seems to be in the ballpark. It has elastic around the hood, but no drawstring, and no pockets. It comes with a small mesh stuff bag. The material appears to be a stronger, more durable material than the Faux-dini.
Now to the question of breathability. As was mentioned in the previous posts, it has a shinier, more raincoat like material, and does not appear to breathe nearly as well as the Faux-dini. Air definitely permeates the Faux-dini much better. I pressed my mouth against the Faux-dini and air clearly passes through. With the Rockbros, the material flexes outward like a balloon and doesn't seem to allow much air through at all. I realize that this is not a truly accurate test, but its not nearly as pourous as the Faux-dini. I have a feeling its going to be "semi-breathable", kind of like the Dri-Ducks material. It does have vents in the armpits which may help some, and it did come with a tag like the one pictured in the eBay ad assuring me that it had good moisture permeability, and of it's ability to allow body vapor to pass freely (they misspelled it) between the membrane. I am hoping they are right. I would have taken it up to the mountains today to try it out, but I am nursing an ear infection so that will have to wait about a week.
Because it looked like it might be geared more toward rain than wind, I threw it on and took a shower. While I believe it would get you through some drizzle and light rain if needed, it is clearly not a rain jacket and soaks through under the deluge of a shower fairly quickly. Its water resistant, but definitely not waterproof.
Bottom line - Size wise, it is exactly what I was hoping for. If it breathes a little better than I think it will, it may be a valid option for people up to 6'5" or so. I'm not sure yet if I will be taking it on a thru-hike, it will need some field testing and I have some concerns about the breathability. But either way, it will likely find a place in my daypack.