Time Warner recently upped my speed to 300/20 Mbps, which is nice. If I use their supplied Arris TG1672G Moden/Router in regular mode, i am getting about 325/22. If I put it in bridge mode and use my own router (a Cisco/Linksys E3000), the (wired) speed drops to around 180/20. Would a new(er) router help with this? I prefer to use my own router.
You would have to get a new router, but that can be a bit of a pain since you will need one that can do gigabit on the wan side reliably. My vote would be to just use their router and use your old one as just an access point.