Russ, I bought the first one shown at the top of the page, Item #1GMHM. Actually, I bought that one but with the light (4 leds), but that was a waste of money. Not bright enough. Tossed the light into the trash.
I first bought a flourescent magnifier, but it seemed to always be in my way, and kept moving around. The headband solved all that for me because I can just flip it up when I don't want it, and it's always positioned to where i"m looking. I bought the glass unit because that doesn't scratch easily, just breaks if one drops it onto a cement floor!
Their quick action in getting me a new lens plate and at no charge is what really impressed me, but the unit is well built, and the lens plates snap in and out easily for changing the magnification. I wouldn't be without it.