I recently purchased the barrel band shown in your link for my Dreamline Classic, I didn't experience the extreme droop you describe, actually, I experienced very little if any droop, but I wanted the extra piece of mind stability between barrel and air tube while out woods-walking.
Back to the band,,, I'm not wanting to sound as though I'm trashing the quality of the band as some have, it does what it's meant to do, but if you want pretty / attractive, you probably shouldn't buy one.

I cosmetically altered mine, using a hacksaw - making top and bottom half inch wide - removing one of two screws, and a vice-held belt sander to clean up the hacksaw cut and the top block thingy? that must be part of the 3D print process, 'cause it serves no purpose. My finished "look" (and I may do more cosmetics) is much more like a barrel band that I envisioned should look like. I also opened / smoothed the top barrel hole slightly with sandpaper on a dowell which allows easier slip-on AND provides the same feeler gauge thickness between the shroud - tank measured at the rear as it measures at the band. That dowell sanding also allows the barrel shroud to move "ever-so-slightly" which as I would believe makes it still free-floating, yet provides the stability I was wanting.
The weather here has not been conducive to outside shooting for comparison of my un-banded results, but I feel pretty confident that I'll show little to no change.
In seeing the Ebay band in the previous post, had I known that was available, it would've saved some work for sure, it looks pretty nice for less money too.