Phone-based Mixed reality Headset for UE developer

Asking for information/vision from experience developer. which Phone-based Mixed reality Headset is suitable for developing MR Content by using unreal

  1. Mira Prism (Single reflection) https://www.mirareality.com/


2. HoloKit (Double reflection) https://holokit.io (Also seebright…)
2017-09-24_10-05-50.png

do you have other type of MR-Headset (Phone based) more than this? for me Mira Prism is looking good, light weight. since it use only single reflection I think the image quality may better than HoloKit but may need to flip the output image.

P.S. Sorry for my English.

Thank you.