My DVD is running custom firmware now, Region Free and I detect the media ID on each disc and burn beyond their max speed ratings safely. Full dual layer support as well. I also rewrite the DVD ID on the fly so old DVD players read it in the best compatibility mode.
If this is what you want and you don't mind learning technical information then go here:
http://forum.rpc1.org
If you just want something off the shelf then you should read the latest reviews in the magazines, if you have a library nearby visit their A/V section or whatever they call the section they store magazine subscriptions in.
You can also check out macworld and do google searches to help you research.
Good luck!