Just cancel your Mediacom and have no regrets. Mediacom has such horrible customer service not to mention their prices and quality and reliability of service sucks too, best decision I ever made was ditching them. I even gave them a chance to retain my business by telling them I was looking at making a switch to satellite and if they could offer me some of the great deals they were giving new customers I would reconsider but they wouldn't budge and gave me the BS line that they can't offer any promotional deals to existing customers. Funny how when I called to cancel they did exactly that though! I had planned to keep their cable internet but was told that since I no longer had a TV package the price would go up so I did the same thing, told them if they couldn't offer me a deal I would be calling back soon to cancel that too after I setup DSL and once again they wouldn't offer me anything until the last call I made to actual cancel service.
Even your dish companies will offer you something if you've been a customer long enough and tell them you are considering switching to their competitor. You aren't in any kind of contract with your cable provider so cancel and reconnect at will as you have all the leverage on your side. If they want to keep your business bad enough they'll do what they can to satisfy you else you just cancel and move on.
