TWC offers Road Runner Turbo, which is 20-25MBPS, for 39.99/mo for the first year. Not sure what it goes to after that.
I definitely think you're getting ripped off. There's no reason to pay that much for so little. My friend used to use AT&T (before switching to TWC) and he didn't even get the speeds he paid for. After switching to Road Runner basic, which is 10MBPS, AT&T called back and tried to offer him their "highest speed ever" of 3.2 MBPS. Needless to say he's still with TWC.