Opinions on lightscribe = too slow for serious labelling. And since you burn a serious amount of DVDs (if you're serious then I'm excessively serious :p) I wouldn't recommend it. 30mins for a somewhat blurry label that's limited to monochrome doesn't justify the cost nor the time it takes. So while you're done burning and verifying 4 discs, you've just finished scribing a single DVD. Not good. And you can't scribe one disc and burn another without having more than one drive - I have 2 lightscribe-capable drives and they're still not fast enough at scribing to cope with a single burner's output.
If you're really serious about labelling, get an inkjet printer that's capable of CD/DVD printing. Many consider the quality of inkjet discs from good brands as some of the best. Lightscribe discs are good too, but since they're too slow I encourage serious users to go the inkjet printing way. I'd seriously say that the old farts of the forum are behind me on this one.