If you intend to wear your belt at the same tension every time it's on, I guess they're fine. I don't use a belt that way.
I'm thinking about buying a new belt because the one I've been using is already quite old and worn out. I would like to try a 3 inch one. I live in Europe and it is very difficult to find them here because they are all 4 inches. I found a 3-inch model on the Internet and it is a lever. Until now I have used buckle belts. I wanted to know if the lever belt closure system is perfectly valid for use in lifting weights.
If you intend to wear your belt at the same tension every time it's on, I guess they're fine. I don't use a belt that way.
If you're in Europe, the folks at 9for9 have a large collection of very nice belts, including 3" with prongs. After screwing around with a 4" belt from Strength Shop, I ordered mine there at the advice of my SSC and haven't looked back.
Yeah, I am from the thrid world too and I ve never seen a 3 inch belt around here (and I know that Rips recommends these for deadlifts). Same problem with lift shoes, in my country we only have one man who makes them in an artesanal way, in a far province and he takes his time to send you his product. This man has the whole lift shoes market of the country, Lol, just to figure you out our situation.
Not true of all lever belts - The SBD belt is more easiy adjustable than a buckle belt, all without having to take a screwdriver to it. And you can lever it so tight it will squeeze a shit out of you, unlike a buckle belt which isn't as easy to get tight. Once you've used one there is no going back to a buckle, at least for powerliftng. Expensive though, and only available in 4".