there is no simple answer to this question, and what is true for one person may not be true for another. For instance, some countries have DVD+R discs cheaper and higher quality then DVD-R, but where I live, the opposite is true! I can get a piece DVD-R for $1.50, and get them as low as $1.25 if I order 50pcs. For DVD+R, I'm looking at between $3.00-$6.00 for 1 piece, and about $2.10ea if I order 50pcs.
Then there is the speed issue. DVD+R can be burned at speeds of up to 8x on some drives, however the quality appears to be sacrificed! DVD-Rs can't be burned at 8x yet, although it is in the works. On the other hand, you *CAN* burn a DVD-R at 1x, and you can't burn a DVD+R at 1x. So for compatability enhancement, and higher quality burns, you can do a bit better with the lower quality DVD-R media then you can with the lower quality DVD+R media.
Of course, DVD+RW also has some other features including a sort of defect managment, which I don't believe any drives support yet, and I think I may remember hearing something about DVD-RW working on something along the same lines. But then again, for re-writing, the best format is probably DVD-RAM
So, basically, it's not as simple as one format being better then the other. THey have their advantages and disadvantages, and every country has different types available to them, and different prices/quality levels. All we can really do is share out experiences with other users in the hopes that we can steer some new users in the right direction.
That being said, DVD+R media in Canada is all made by Ricoh, whether the brand is Fuji, Maxell, Memorex, or Sony, and it's *ALL* over priced! [xx(]