I think it depends on the material. I wear a 26 in TR and I can wear anywhere from 25-27 in R&R depending on the material. The not so stretchy ones I wear a 26 or 27 and the stretchy ones I wear a 25 or 26.
R&R is not consistent in sizes... at ALL. I have a pair of berlins that are tts, a pair of nirvanas that run small, and a pair of jaguars that run big. Your best bet would be to go try them on, or ask on authenticforum where all the denim experts are.