For me, CocoonJS is better in the FPS department.. At least with my latest title... 60+ FPS and ~20 to 35 with XDK..
And actually, if you're a Premium (which you can get free anyway) member like myself, that 30MB upload limit goes to 200MB.. You can't do over 50MB anyway, because Google limits up to 50mb for single APK files, which is why you need to use proper image/audio compression tools..