The proper format depends on the systems your client has in place.
I'd pick a suitable production format for that. Also, H.264 is a very lossy intraframe codec that should never be used for further production or archiving. You should also gently educate your client to the face that QuickTime no longer is working on or guaranteeing support for h.264 QuickTime. MOV's that are really mp4's playback just fine. The big problem is rendering to the MOV container.
If the client really needs the movie as h.264 in MOV format then just use the AME to render an MP4 and change the extension.
