This vent panel is 46mm high instead of standard 44. If you use more than three in a rack next to eachother you won't be able to screw in your rack gear anymore. I bought Adam Hall rack rails and if I stick two of them together, then the third one already can't be screwed in. It's not a big deal if you always have some rack gear inbetween, because the bent parts ten fit it nicely, but when you're rack has more empty space and you want to fill it with these vent panels, forget it.
Otherwise they are solidly built and look nice in a rack.