Disadvantages of choosing Silicon Valley as your startup's hub?

What are some of the cons of being a startup in the bay area?

I don't have first hand experience with having a startup in Silicon Valley, but I would imagine that:

1. Local talent is really hard to find and hire, given the competition, so you better have at least a founding team locked.

2. Cost of living is probably higher than in many other places, so bootstrapping could be a challenge, especially for founders with families.

3. You are surrounded by a lot of self-made millionaires and serial entrepreneurs, so as a first time founder you could feel intimidated or at least have some self-confidence issues.

4. I am under impression dating is really hard in the area as you sort of have to find someone in a similar stage of success.

That said, there are so many advantages that absolutely have to be considered as well.

Here are some:

• Risk of top employees leaving to join or start another startup. On average, people don't stick around for a more than a year or two at the same company in the valley. This makes it harder to invest in developing people.

• High costs of renting an office space.

• Higher cost of living. Rents are absurdly high in San Francisco.