Alot of people have had problems with these for good reason - they were good discs when they were released initially, but later batches since probably late last summer have had many problems. I bought a spindle about 8 months ago and literally half of the spindle has visible dye defects (in good lighting). And nearly every one of the discs burns pretty bad but useable, even those that don't have visible defects. They are either Ritek R03 or RICOHJPN R02, and I think both have had problems (both are made by Ritek). I've used other Ritek R03 that burns decently from Memorex as well as an older batch of Ritek R03 from Ridata that was sold as 4x media that worked well, but there's a very good chance you are going to end up with crummy media, buyer beware.
Here's a common result from these discs that is RICOHJPN R02, unfortunate as they used to be better quality and some other brands are still good quality apparently. If you buy these, buy them knowing that you are probably going to end up with discs that don't burn very well as most of the later batches being sent out are not near the quality of the early batches.