I bought the Solid type (10 inch) and they sure are solid. I am using them currently over about a 3 foot span, and I have easily 200lbs on it. Installed in less than 5 minutes, but that was into studs, not drywall. I wouldn't recommend installing in drywall alone, unless it's for lighter weights... Not because of the bracket itself, but because drywall anchors always seem to be an easy point of failure, no matter the application.

Side note;
There's a review I read where someone shows a picture of the bracket they bent with their bare hands, but they don't even have the provided support piece in place... I would send $100 if someone can bend it in the same direction a load from a shelf would place, with their hands only, with the support in place... the comment is extremely misleading, and either they didn't care that they were misleading, or they're ignorant of how brackets/shelves work.

It's made of thick

I have solid wood floating shelves that are rated for a few hundred pounds. However, not wanting to trust that, alone, I picked these up and while it does add a little complication for closer shelves, it does provide the strength so I feel comfortable with setting more fragile items, like my desktop, beneath the shelving.

These appear to be cut by punch press instead of waterjet/laser, the holes are very sharp. If you have the time/energy they should be deburred. We installed them in a shop environment where it's less of a problem.

I bought this to hang an old truck toolbox on my shed wall to get it off the floor. I wanted to reclaim floor space while also make it harder for mice to make their home in the metal box. This brace did the job perfectly; it is just wide enough for the truck toolbox to sit on securely. It is now on the wall of the shed and I have much-needed floor space. I would definitely buy again!

These are very good shelf brackets. I ordered three pairs of the 12 inch size to be used with 14 inch deep shelves I built from plywood for a laundry room storage. The only reasons I didn't give it five stars were (1) One of the six brackets was slightly bent/warped and so the front edge of it does not line up along the edge of the shelf as all of the others do nicely. If this was going in a more high visibility area, I probably would've returned just that one or ask them to replace just that one, but rather than go through all that hassle, since this is in the laundry room we're only my wife and I are going to see it, I'll let it slide this time. But it bugged me, since as a whole they are quite beautiful and well-made.
And (2) the screws That it comes with, although they were all there and they had both the longer screws for the side you'll anchor to a wall and the shorter ones for going into the shelf itself from underneath, they are not self drilling screws and they were Phillips head. Please, please, please, every company out there please listen: do not use slotted or Phillips screws anymore! Use screws that accept square or torx /star shaped driver bits! They are SOOOOOoooooooooo much better. It would probably add $1 or less to the cost of this product to provide high quality self-drilling Torx head screws. Yiu could even include a driver bit. People will love you even more for that. Phillips and slotted are so 20th century. Ugh. But the brackets seem to be great. Nice that I could put a couple hundred lbs per shelf no problem in these.