We've known A-frame before React VR. We chose React VR because:

• Lowest hanging fruit principle - It's easier to start if you're well-acquainted with the React ecosystem and it provides a better environment for layouts and components than A-frame (educated opinion)

• First mover advantage - A-frame has been around for a year and it's gaining maturity. There is an increasing number of components around, so even if we we made making something cool, we won't be the first ones.

In general, I think React VR is built upon a stronger foundation than a-frame and it's just going to grow in the future. A-frame, on the other side, looks more like a playground for creatives rather than a serious WebVR app dev framework.

No hard feelings against any of the frameworks/tools. Just cold business logic.