Thanks for your interest in KnownHost. Both datacenters we are very happy with. In California we use Verio and Cogent (like you said). In general Cogent isn't on the same level of Verio but it is a good mix. In Texas we use Internap and Level 3 which are both premium. We do have a full 30 day money back guarantee if your not satisfied with the datacenter.
Cogent has a certain stigma about them, but having a plethora of recent experience with them (especially in many key locations such as San Jose), I would not say that there is no such thing as worse bandwidth.
There is definitely worse out there, trust me. Besides, at this point, Cogent has adequate peering to all tier-1 ISPs in the San Jose area. They have had congested peering issues with AT&T in certain locations, but in San Jose it has been fine. Next, they lost peering to Level(3) some years ago, but this is something that is a one-off thing. I don't suspect that it will happen again, due to the major outrage that came as a result when it did happen.
Furthermore, many ISPs who use Cogent are cheap in other ways as well, i.e. they oversell their bandwidth to an extreme extent which in turn congests their pipes, and obviously will make it "seem" as if Cogent bandwidth is bad, when it's really just their misuse/abuse.
Cogent doesn't have the best latency, and I wouldn't recommend them for a gaming network. But, for straight-up web hosting, and with Verio in the mix as well, you cannot go wrong with the California network that KnownHost offers.
Take this from someone who has been working with tier-1 carriers for several years...Cogent is quite good (especially at this stage).