We were lucky to share our office with a YC company when we raised our Series A. I must have bugged one of the founders every day for advice on terms and which partners were cool. But now we're all just scaling like crazy and there isn't that shift up the chain towards new mentors who have gone from e.g. £10m p.a. to £100m p.a. revenue. Those people are rare overall, but concentrated in the Valley.
We were in Royal London House with GoCardless and Smarkets. They were (and probably are still) about 1.5 yrs ahead of us in many ways. We also are lucky to have an early investor who is on the board of Zopa.
Most founders I know who have progressed for a few years have at least one or two founders under their wing informally.
I've seen firsthand a surprisingly large number of startups that make a profit from day one. And a lot of startups that were funded from nonwealthy founders' savings. My impression is that we do stuff on a smaller scale, but it tends to be more reliable.
Of course, if they're the only London startup you've heard of, maybe there's a bias. Crazy ambition can garner a lot of PR, especially when it succeeds. :P
One of the reasons I started organising the LDN2SFO trips was to expose more Brit entrepreneurs to the collaborative culture in the Bay Area in the hope that they would bring it back to London.
This is what's wrong with media today...