I only took 7 instead of 7R because I did not have it. I know "R" stands for "reviewed" by AAMC. But does this significantly change the score you get? Are the scales different?
There is 3R-6R, 7 and 8. 7 and 8 are new, not revised because they were written for the newer version of the test (unlike 3R-6R). People mean 7 when they say "7R".