At this point, if a device doesn't support CD-R, its junk or VERY old. CD-R discs have been around for about 10 years so support isn't really an issue anymore. Of course, that doesn't excuse poor writing quality which can and will cause compatibility problems.
The DVD writers from Optorite and Plextor can pack more data onto a CDR disc, but they use special technology. Discs burned by the Plextor are sometimes supported by other drives, but the Optorite's are not.
I would hope that we'd see less DL complaints in the future. The technology is no longer "new" so there's no excuse for manufacturers not to support it.
"Blu-ray is just a bag of hurt." - Steve Jobs