As an old Roland D10 owner, I can tell you that while the D10, D20 and D110 have the same patches, the D5 has a completely different set of Patches and Timbres to the aforementioned even though it is essentially a stripped down version, sharing the same architecture which means it should be Patch compatible without the effects of the others of course.
Also, the D50 and D70 were completely different beasts, even though fundamentally based on Roland's LA architecture, they're not Patch compatible.
As I've some experience of this subject and I've seen this topic come up reasonably regularly, I decided to write a refresher post, especially since some of the older posts are now referring to online resources which are no longer there.
Hope this helps:
http://forum.cakewalk.com/Instrument-Definition-Files-Cakewalk-Sonar-INS-Files-m3716587.aspx Cheers! :-)