The RN did not fit RF at all in my previous car. I haven't tried it in my new car, but I think it would fit since this car is roomier. It fits fine in my husband's car. I had no problems fitting the MA... so, if I hadn't been able to try out the RN in person before buying, I personally wouldn't have bought it.
Also, even though it fit in my husband's car, it was at a 45-degree angle that I could not adjust no matter what. I prefer a more upright installation so that alone would deter me from buying it for RF use in my situation. I've seen pictures where other people have been able to get it more upright, though!