Since the Penguin update and with the reality of the SEO industry nowadays, I would recommend a large site.
It seems that building an online brand is crucial in terms of SEO. One site with 1000 inbound links will be more powerful than 10 sites with 100 links.
On top of that, I have seen better conversion rates on big sites with multiple sections than on small targeted (satellite) sites. They look more trustworthy and less spammy.