really? i've been using SXM for over a decade. i've never seen a company that is so desperate to keep their customers. they'll do pretty much anything you ask of them.
tired of paying the bill? then don't. they'll cut it off after a few months. then they'll call and be willing to forgive the past bill, cut you back on, and you probably won't even have to pay it for another month or two.
whenever whatever deal i'm on expires, i simply call them up and tell them i'm thinking about cancelling. they'll usually offer something like service for $5 a month, if i'll pay for 6 months at a time or something.
i've never had even a hint of trouble with them in the last decade.