There are also 400 MBit cables. But as Alex already said, when surfing, the bandwidth in these ranges hardly matters; what counts is the latency and the power of your computer.
The latency thing could really be it. I never gave it much thought. Good tip. Well, not just for surfing, here incremental backups of the servers are also written to me from RZ every night. But it doesn't matter if it takes 3 hours instead of 1 hour..