I bought this kit from RS at the beginning of January, I spent 4 days putting it together and then discovered the following issues:
The drivers are not compatible with windows 8.1
The Micro SD card that they provide with the kit was broken (apparently a known issue)
The optical sensor value changes depending on the lighting conditions so I could not get the bed to level as the end stops would not work
The Microcontroller duet board did not come loaded with a firmware that would work, You need to read up how to flash this.
Needless to say the kit is on its way back to RS as it was not as described on the Website.
I have ordered a flashforge creater dual which is due to arrive today