I just saw this post by Robbie Elder on the FB Yamaha RC Group Page. Excellent and hard to find summary info on 9000 series drums.
"RF is the Power Recording Custom, so I’d have to disagree that the only Recording Customs are the drums with the RC suffix. The RC and RF drums were released at the same time, and all Floor Toms had the RC suffix, even if the rest of the kit was RF. Both 9000 and Recording Custom are in the title, so I don’t see the problem with allowing both. In my experience, most people don’t know the differences between all of the different model names, and these groups give them an opportunity to learn about them.
Also, when you factor in the drums that were sold only in Japan, you have A, AE, B, D, DA, E, G, GA, GE, R, RA, RC, RD, RF, RG, and RP. You also have RCD (Turbo size) and RCR (virgin) versions, and I’d also count the original YESS Recording Customs with Y, YJ, and YT, as they still had a 9 in the model number designating them as 9000 series.
There were so many model name changes in the first 10 years of the 9000 series before the use of the Recording Custom name. Even though the early 9000 series aren’t the Recording Custom, I would consider every version of the Recording Custom that has a 9 in the model name to be part of the 9000 Series. The only Recording Custom I wouldn’t refer to as the 9000 Series is the new one that is no longer made in Japan, and that is only because the new model name system doesn’t have a 9 in the model name, not because of where it is made. The early 9000 Series drums made in Taiwan (D, DA, & E) are still 9000 Series drums."