I have never had it either.
Except for myself
But I have heard people speak so highly of it, how it has literally saved their horses' lives, and I'm sure any horse could benefit from getting checked out by the chiropractor.
Are you sure that your tack is fitting correctly? Saddle soreness could be an issue. A professional saddle fitter could also be beneficial to you, but I think a chiropractor will probably be able to assess things from a more medical perspective for you.