AFAIK cios38-r21-d2x-v3 seems to be a good replacement for cios38-r17. Is there any reason I would not wan't to replace cios38-r17 with cios38-r21-d2x-v3. From what I have read and tested, compatibility should be the same or better with cios38-r21-d2x-v3. Is there any known downside?