Here are the results* from a 200-click solo ad I bought from Paul de Sousa. You can find more reviews in my solo ad directory.
Clicks bought: 200
Clicks received: 269
Optin percentage: 33%
Cost Per Optin: $.29
You can find Paul de Sousa at his website
*These are the results from my squeeze page and sales funnel. Your results may vary from mine.