[jakejake]

I've interviewed before where, once the offer was made, they did want me to decide rather quickly. This was a startup that was reputable, popular and growing extremely quickly. However they didn't make me feel as if I was racing against other candidates for the spot - they just wanted to get to work.

I would just make sure to do your research and see if you can find anything about this company or the main people involved and decide if you trust them.

By the way - most startups will fail. That is the reality. If you are going to work at a startup you need to be willing to make risky career moves.