Never, ever burn your DVD's at the maximum burn rate. (You will make a lot of coasters if you do). Pick a speed in the middle; 4X or 6X is my personal limit. Out of hundreds of DVD's over the past ten years, I've only had to replace two.

I recommend that you use the freeware "DVD Identifier" to read the media ID to learn who *really* made the discs in your box:
http://www.afterdawn.com/software/cd_dvd/dvd_tools/dvd_identifier.cfm

DVD Identifier has it's own database to interpret the media ID into the manufacturer name and write parameters. Likewise, your DVD burner has a similar lookup table in its firmware. If your burner is relatively old, then newer DVD manufacturer's codes won't be found. The tipoff to this is when your DVD burner falls back to "safe" parameters, like a maximum burn speed of 2X. Some older burners revert to their max burn speed, like 24X, which almost never works. If this happens to you, then you need a firmware update or a new DVD burner.

More info here - Article From:
http://www.digitalfaq.com/reviews/dvd-media.htm

Who Really Makes the Disc?

Realize that most media is produced by a relatively small number of factories, located in several different places. These factories are mostly present in Taiwan, Japan, Singapore, Malaysia, China and India. There are more, but those are the largest ones. The best media generally comes from Japan, Taiwan and Singapore. The worst typically comes from China and Malaysia.

The blank disc brand name on the package means almost nothing. Apple is a great brand, but they do not make their own discs, instead outsourcing to a company like Mitsubishi Chemicals. Common companies like Memorex, Maxell and Imation all outsource to media vendors. Mitsubishi also makes the discs for Verbatim, etc.

It is the media ID that is important, as it reveals the disc manufacturer. Unfortunately, this is not written on packaging or anywhere else. Companies want consumers to be oblivious to this sort of behind-the-scenes information. The Media ID is also used by your DVD burner to determine the burn parameters which includes the maximum burn speed.

After you've checked all Steve Mann suggested above, you might also consider burning first and printing later. That way you'll have less wasted ink if you still get coasters. Just don't print a wrong label on it ;)

" Imation all outsource to media vendors"

I think Imation now owns TDK

I have had mixed results with CMC. (Some wag said that it stands for "coaster manufacturing co.")