It's only my experience, but I haven't noticed (as yet) any difference in compatibility between DVD-R and DVD+R set to DVD-ROM with bitsetting.
Some +R medias I used have had compatibility problems even when set to DVD-ROM, but were rejected as well by a standalone player that can accept +R, so my guess was that this is more media related (Brand, MID, reflectivity...) than -R / +R with bitsetting related.
I think a more important question is WHICH +R medias give the best compatibility with standalone players...
In this area, I never had any reject with genuine "made in Japan" +R Maxells 4x and 8x (MAXELL 001, MAXELL 002). I don't have much experience with other +R medias, though I had success with RICOHJPNR01 but I only burned 5-6 of these.
Had rejections from standalones with RitekR03 and, surprisingly, MCC003. :eek: