We should probably draft up a FAQ to add to the first page, starting with these, since they get asked like every other page:
1Q. What's the difference between CatSFC and CatSFC Plus?
1A. Plus has better sound, but lower performance as a result.
2Q. Is <insert core name here> as good as it will ever be?
2A. RetroArch on the 3DS is still a young project, so probably not, no. Just keep an eye on progress.
3Q. What cores have dynamic recompilers (dynrec/dynarec)?
3A. PCSX-ReARMed, picodrive (for 32x and svp only), and gpSP.