Site templates to buy for SP2010

We are looking to buy site templates for common functions in our company e.g. for HR, Finance, IT etc. etc. So I have a few questions:

1. Is buying a site template good idea? I remember issues while upgrading Fab 40 templates from 2007 to 2010 
2. Recommended site or company to buy from
3. People who are using commercially available templates please share your experiences.

Thanks