Yes, I have taken them out for a test ride. I do believe they make a difference, but it is always hard to tell just how much without taking them off and on to test. My slightly larger version should be the best test. It's a bit cool today and not t-shirt weather, so I cannot speak definitively just how well they work. When I ride in a t-shirt, the wind from down below just beats the crap out of my shirt around my neck from the air that comes up from down below. With a jacket on, I don't notice it nearly as much. I don't expect a miracle, but my opinion is they will be an improvement judging by what I can feel with my hand and around my gloves. Nothing ventured, nothing gained and it's only money!
I just submitted a request for a quote to have my new panels laser cut out of high-impact acrylic. I have to wait on that quote before I can order. I'm really happy with how they look, as they almost seem invisible on the bike.
Your clamps look like they might be a simpler option, not needing mounting bracket to change the mounting holes from horizontal to vertical. I think my clamps were like $16 each which wasn't cheap. They are really nice CNC machined aluminum clamps and are well worth the money. I may post more when I know more...