Depends entirely on the practitioner, from what I see of people who go to them.
There are some who are really really excellent.
There are others who tell everyone they have a tilted pelvis because one leg is shorter than the other – and seem to actively encourage expensive dependency amongst their patients.
We had a local one who managed to carry on practicing despite having been removed from the register by the General Osteopathic council – for reasons which seem rather harder to find out than those for which Drs get struck off…
And don’t believe anyone who trashes all physios… (and I am not a physio or chiro or osteopath).