Nobody has pinned down conclusively why the Ritek G04 problems are happening. But, I'm willing to bet that it comes down to either quality control inconsistencies at Ritek, or configuration problems on user PC's, not the NEC drive itself. I've had no problems whatsoever with the Ritek G04 4x -R discs I've burned, under the configuration in my sig.
I have no way of knowing others' configurations though, such as whether they have problematic IDE drivers (read NVidia ForceWare or Intel Application Accelerator),what apps were running on their machine at the time they made the burn, or what the fragmentation level was on the hard disk they sere burning files from. It could be that a number of issues are contributing to this problem and that since so many people have bought Ritek media and NEC drives (after all, both are economically priced) that it just appears that the media could be the problem. Or, it could be that discs coming from Ritek are varying enough in quality that some batches have a high error rate.