I ditch and switch every time a contract runs out. It's a complete non-event once you've got your own router, usually just need to update the username and password. Everything within the house remains the same - wifi details, IP reservations, whatever. Last switchover the disruption amounted to it disconnecting at midnight on switch day, then reconnected 5 minutes later to the new ISP. Done.
Currently paying Shell Broadband £25 a month, but got a £110 amazon voucher and £65 cashback for switching to them for 18 months. Works out at about £15 a month all-in (assuming there's something worth buying on amazon).
But this is irrelevant to the OP, who doesn't have a BT line. So has a choice of crap, expensive Virgin, mobile or satellite. I'd recommend mobile, but definitely worth telling Virgin you want to close your account to find out what the non-mug's price really is. They all play the same silly games, you need to either switch or at least threaten to. Unfortunately this is a symptom of most people being too lazy to care, they take advantage of it.