We were advised by our physio and our paediatrician not to use one for our DD as puts to much pressure on babies hips (among other issues). Because my DD had mild hip dysplasia I did not want to take the risk!
Ditto. It's a no from me. Nor will I use Exersaucers or crotch-dangling carriers, or baby walkers (can't believe that those things still exist) I used all three as a baby and I have terrible hip and lower back issues. None of this showed up until I was well into my twenties, but I absolutely believe it contributed.