I terms of the HTC Vive the only burning issue I have at the moment is the problem of no sound. It seems to effect anything I am playing on playcanvas (not just the VR based stuff) on Chrome Experimental. Other websites like youtube seem to work fine and play through the Vive but playcanvas projects don't. At the moment I am not sure if it is a PlayCanvas issue, or Chrome Issue , or Local Issue. But because my ultimate aim is using it for presentations with voice overs its effectively a non starter at the moment. Does the playcanvas team have a HTC vive setup? I could really do with someone seeing if they have similar problems in case my problem is only a local one.
I have another smaller issue with the VR mode in that it doesn't seem to support room scale to well. I know there are demo examples on webvr.info and one of them shows the differences with room scale. So for the VR mode to work well it really need to be room scale aware.
aFrame is moving very fast and it's going to be important for playcanvas to keep up. Currently there are no audio problems on aFrame and there are no room scale issues either. Their editor is apparently in Beta phase although I have not seen it yet. Yesterday I saw someone create a application to play sound and show album covers from spotify's api in less than 50 lines of code. Playcanvas has loads of features it lacks (at the moment) so it just needs to get the issues out of the way to attract and keep developers.