These are great, I've used them for acoustic guitars, electric guitars and ukuleles.
The quality is good for the price. Sure, they have some rough edges and some of the "arms" (the things you put your instrument on) are a bit more tight on some of them. (I've got a lot of them, this "issue" is prevalent on some of them but honestly it's not a big deal.)
Worth noting that these doesn't come with screws so bring your own.
Overall, these are great and for the price they are amazing.