I've ridden his horse every day for the last week, and OMG my butt bones* hurt so bad I can barely sit. Lucky for me this was only a one week gig, because my brother is taking his horse back up with him, and is going to ride the horse himself.
However, despite the enormous amount of uncomfortableness caused by riding two hours a day on a bouncy horse (I decided it wasn't my fault), I think I'd like to continue riding, as it's always been something I have loved to do. Maybe I'll get one of my own lazy horses out of the pasture and ride them.
What I should really do is ride my mare and lead my colt along behind to get her halter broke. Pictures of my colt to come later.
*Yes, I know "butt bones" isn't entirely anatomically correct nomenclature.