1. ElasticFunnels
Affiliates who split-test paid trafficStarts at $97/mo. Free trial: 14-day, no card.
ElasticFunnels is the pick if you buy traffic and live on conversion rate. It rotates split-test variants under one URL so your ad learning survives, and it keeps the page, the checkout and the attribution on one record. It is newer than the incumbents, so run a test campaign on it before you move a whole business over.
Read the full ElasticFunnels review