The pro’s – you have them, they are free, and the chickens should like them.
The con’s – none I can think of but I’ll mention a couple of things to watch for.
If your chickens sleep over an open top nest they will poop in them. As you can tell by the other responses lots of people use open top nests without a problem. Most of the time having your roost higher than the nests and away from them prevents this, but there can be times it happens, especially when you’re integrating. If it does happen it’s usually not that hard to fix.
I’m not sure how high that lip is. It’s possible the chickens will scratch out the bedding as they are rearranging the nest to lay their egg. It may not be a problem at all, only time will tell. If it does happen the fix is easy. Even with that shape, just add a strip of wood across the front to raise the lip a couple of inches. That’s a lot easier than building a new nest.
I like the overall length and width of them. For comparison mine are 16” x 16”. Those crates are certainly not too big.
I don’t know how you plan to install them. If you leave the top open they will be fine. If you stack them or put something over the top to limit height, I’d go up a few inches. I’ve had hens use an opening 6” high and 8” wide to go into a nest. If you have to raise the lip they might need a little extra head height to get in and out.