Here are the results* from a 100-click solo ad I bought from Craig Raphael. You can find more reviews in my solo ad directory.
Clicks bought: 100
Clicks received: 96
Optin percentage: 42%
% Tier 1: 15%
Cost Per Optin: $.75
You can buy a solo ad from Craig at his solo ad page
*These are the results from my squeeze page and sales funnel. Your results may vary from mine.