The Walkera is a curious one, people have tried to dismiss it as tat, which actually isn't fair, it's using an APM controller, so uses the Arducopter software that is fairly mature and has some great power features, so that alone makes this copter interesting.
The downside which is puzzling, is the APM is considered to be at the end of its life, from a software viewpoint, future features are due to be on the Pixhawk only. If these future features were just gimmicks then it wouldn't matter, even now the APM will do 99% more than photographers need, but some of the features of the Pixhawk are good for safety such as dual GPS, the EKF (an algorithm to spot faults) and in the pipeline sense and avoid.