To update - I've acquired the Adelphia cable so far with pretty good results. Have 2 machines networked off a Netgear switch, with my server machine running Sygate Home Network. The cable can certainly handle the data stream, although I suspect Adelphia's backbone is not of the highest quality as pings are sometimes not great. Outages have averaged only several per week, usually not more than several minutes at a time. Installation of the service was very easy. My server machine is also set up to dial Earthlink via a 56K modem should the cable fail. I feel Earthlink dial-up service is excellent as a backup.
My biggest problems relate to running IB behind a firewall. Even when the ports are open to IB (and I'm no techie so I may not be doing this correctly), quotes can be bad. QCharts seems to run fine behind the Sygate's NAT function, but I cannot get NexTrend to run on either the server or the client machine. IB seems to be healthy, at least the old TWS which I still use, when run from the server. Something to keep in mind for those of you considering the networked route.