I do not bother to track anymore, there are over 100 models of the same model and then they reproduced those models into CS models and R models and then...................ah fuck it.
Made in the custom shop, solid mahogany backs non weight relieved, long neck tendon, R= historic reissue, R7 is a 57, R9 is a 59, and im sure you can figure out the rest. the neck shapes are also different.
Im a big fan of these guitars, they come with a vos or gloss finish for a few hundred xtra.
The main differences are that the R7 is a gold top, R8 is a plain top, and R9 is a flametop. There are a few other small things too. I just got an R8 a few weeks ago. Its really cool, it also comes plek'd, it actually plays faster than many shredder guitars I have tried out and it has a very fat neck.