Router-by-Router experience with Comcast Business Class
Netgear FVG318 - Great multi-function and easy to configure router until a couple years ago... Since then we've had problems using them with Integra Telecom (T1 service) and more recently Comcast. The set-up works fine on installation / configuration but after working correctly the DHCP service would time-out in hours or days for no apparent reason. It was maddening, and replacing the router itself (3 times at one client location, and once at each of two other locations) failed to provide a consistent connection. Assigning internal dedicated IPs forced Internet connectivity but left wireless un-available. Also upgrading to latest firmware did not resolve the problem. It's notable that we had several examples of this FVG318 router working fine with Integra Telecom and AT&T DSL, but several failures with Integra T1's and now Comcast.
Cisco WRV201 - Another fine multi-function and easy to configure router. It solved the above DHCP problem with Integra Telecom and is still in place doing so at one site. But with Comcast it began to sputter intermittently (not every day and not all the time) losing and immediately restoring the connection for no apparent reason while connectivity from the Comcast modem seemed to remain steady. It's notable that 7 Comcast 'Customer Requests' over several weeks were NOT enough to earn a router recommendation like we're trying to offer and request here, or for that matter any diagnosis but that the problem was ours..
D-Link DSR-250N - This multi-function router is a bit harder to configure, but we suspect it has solved the above problems. DHCP works and connectivity seems to be much steadier. We'd like more experience to call it a 'viable solution' for Comcast Business class services. Currently we have one installed and two on order for use with one existing and one about to be installed Comcast Internet customer.
Additions? - If you have positive or negative router experience with Comcast Business Class Internet services and particularly in managing both Comcast 'data' and Comcast 'voice-over-IP' on a single CAT5, CAT5e, CAT6, etc. network cable (e.g. the network connection is from the wall to the phone to a PC) we'd be VERY PLEASED to have you share it here.