I guess it depends on how long you are looking to have the cable modem. I'm not sure about the rates with your company, but when I first had a cable modem, I was charged $10 a month for modem rental, then an exra $40 for the service. I didn't have it too long (because the cable was always down), but if you plan on having it more than a year, then I would say go ahead and buy a cable modem. From what I've seen, you can get some good deals for around $100 with MIR, and this is at retailers like Best Buy, CompUSA, and online retailers.