The most useful feature is the ability to run tests with different combinations of traffic sources. This allows us to make sure that we are optimizing our campaigns correctly. I wish there was an option to use the data from one test in another. If you are looking for a software that will help you automate your marketing efforts and optimize it, then you should definitely look into Instascaler. There is nothing I dislike about the product. I have not encountered anything that would require improvement. We were able to optimize our campaigns and get more traffic to our site.