Comcast supports this, Time Warner does not (or at least not in my neck of the woods.) IMO it's not worth it. I've had years where I've been through two or even three cable modems for one reason or another. That $3 a month is invaluable as it makes it THEIR problem to fix it. If she truly wants to get her bill down as low as possible she should check into DSL or possibly even wireless ISPs in her area. DSL down here is 1/3rd the cost of cable although MUCH slower (1Mbps vs 3 or higher).