Depends. I have only one commercail "ground blind". Don't even recall which brand or model.
I'll set it up and then scrounge limbs, brush tops if any are in the area to soften the outline. And many times I just make a blind from whatever I can find and sit tight, usually leaning back on a big tree or a large rock, or against a steep hillside.
The plusses of a commercial portable "ground-blind" in my opinion are fair protection from the elements, excellent concealment even in the bald wide open, and possibly some scent control -- but I suspect not much from what I have expereinced. I always play the wind best I can when using a "ground-blind".