Is this shaving?

I tried a website on 2 cpa networks that have gateways. On one of the site about 36% clicked on an offer and on the other 63%. The site with lower percentage has a slower loading widget and I was thinking if this is the reason or are they just shaving that much?

Also, trying to avoid this, I would like to try one of those scripts where I can put any incentive offers from any network. Which is the best one and that has the most options?