Chose Optimizely Web Experimentation
Optimizely is my favorite due to its ease of use and exceptional testing capabilities. It is not the cheapest tool, but the other tools that could be compared are not cheap—you get what you pay for. Some of the smaller tools are making gains, though!
Invited by the Vendor
A de minimis incentive was given to thank the reviewer for their time. The incentive was not used to bias or drive a particular response, nor was the incentive contingent on a positive endorsement. TR verified that a representative sample of customers was invited. More Info