I've had several, and currently running one in my F350....they're OK in a full size, not so much in anything smaller (they hang down so low, that only full size trucks will have enough vertical height in the cab to spare without cutting into your line of sight). Currently running without the visors at all in the Ford, and as others have mentioned, MANY people have reported funky visor mounting. On some trucks merely swapping the visors to opposite sides seems to do the trick (drivers side visor mounted on passenger side, and vice versa), others it seems like they use the same flat plate on many models of trucks, and just swap the mounting brackets. I've also read that quite a few taller people, like over 6 feet tall, have issues where the shelf ends up right in their line of sight, or possibly even within the arc their head would travel in a front end collision before the seat belt and/or air bag stopped them)I'm a short troll, so it never bothered me.
They're also made out of fairly thin aluminum, with only a couple SMALL screws on either end holding it up, with the brackets screwed into the factory visor mounting holes with sheet metal screws.....so don't think you're gonna hang a bunch of heavy radios or other equipment off of them. It'll sag in the middle in a hurry...if you're lucky. If not, it'll pull right out of the truck.
The plate itself is also a LOT shorter in both height and depth than many people realize...maybe 4" deep front to back, and maybe 1/2" tall (it's an aluminum plate formed int a shape somewhat like C-channel plate, but the windshield side is angled in). I laughed, a LOT, when I got the Rifle-It "kit" with it. The kit is literally nothing more than a velcro strap that wraps around it. I'd be pissed if I actually paid for that. Most typical hunting rifles are going to be too tall to fit in it if you have a good scope mounted, and forgot about putting something like an AR-15 up there. Then, because it hangs down from the roof so much, it will be plainly obvious to anyone walking by that there's a rifle up there. A pistol in a holster is less obvious, but without adding some kind of dividers yourself, the first time you take a left turn too hard, it will slide all the way to the passenger side along with anything else not bolted down to the shelf.
I use it to have some place to secure the cabling going to me windshield mounted phone, along with a remote mounted head unit for the ham radio, a few extra gauges or other displays, such as a small LCD display I was using to monitor other systems in the Jeeps. But even in the Jeep, I had to add a couple pieces of angle iron to it to keep it from sagging. As a comparison, in my Samurai, I have a 6" wide, 1/8" flat plate of steel, about 36" long, spanning the roll cage tubing,with more weight on it, and no sagging whatsoever.
Honestly, no, I don't think they're worth the money. But, while I have the capability to make something similar myself, I'm lazy, and the $80-$100 I spend on them is cheap enough to not have to mess with making mounting brackets myself.
