Price comparison website?

[cluckcluck]

Thinking about building a price comparison website for a very focused product category (although haven't decided yet)

The main ways I can see this making money is using affiliate payouts and possibly banner ads.

- Does anyone have experience with making or being involved with a site like this?
- How did Google like it (as there may be duplicate content, and non-unique content)?
- Did it actually make any/much money?

Cheers