I've built my first cardboard and have ordered one from "dodo" also. My own creation is currently using the additional Lenses from the Oculus Rift DK2 and they work great. The size of the default cardboard is not big enough for a Note 4, so I've ordered a "large" kit from DoDo. Within the week I have built a dodo kit for my big phone, and I also ordered some components for the regular sized cardboard for my home-made cardboard and little phone.
I've built out Gear VR and Cardboard apps and proven the pipeline. I've also added leap motion support for my lunar prototype in the Cardboard and GearVR builds, and it works great!