I just purchased a Motorola/Arris Surfboard 600 series Modem. I got the SB6183 to replace my Times Warner Cable issued cable modem. I purchased it because I went to a higher speed of internet and I would need a new cable modem anyway, which they would eventually send to me. Secondly, they are increasing the price of the rental of the modem to $9. a month. I got this one pretty cheap, so in little over a year this new modem will pay for itself.