Is there any reason you've eliminated the possibility of using an external USB2 DVD burner on the Mac?
Pioneer, Sony and Samsung burners are excellent, Mac or Windows (or even Linux). A good burner is a good burner, and is platform agnostic. It just happens that Mac, like most PC OEMs (Dell, HP, etc) use cheap LG or Panasonic/Matsushita drives. Apple cuts corners, too -- it's not all premium gear like the company and rabid fans make it out to be. (The hard drives can be lousy, too, so always keep yourself backed up! And I don't mean to a Time Capsule! Stray from the Mac cult, when buying peripherals such as hard drives.)
Actually, I think it's a good idea to have a good burner in both of your systems.
Slightly off-topic:
Macs are great for editing and authoring, if using Final Cut Studio (Final Cut Pro + DVD Studio Pro). Is that your setup?
Note: If you've mentioned this elsewhere, I don't remember. Just tell it again.