Have you checked to see whether one of the
WRT-based firmwares would work on your device? I run DD-
WRT v23 SP2 on both of my Broadcom-based routers (an old Fon-supplied WRT54GL and a Buffalo WBR2-G54S) and it works really nice. The Tomato firmware (another
WRT-based firmware), if it's compatible on your router, has some really nice Web UI-based bandwidth statistics which update in realtime, I'm going to try installing that on one of my routers but I can attest that with DD-
WRT, and a little trivial configuration, both my routers work really nicely.