We chose the RA55 over the MA70. Although I figured it was just an illusion, it seemed like DD had more RF growing room in the RA55 over the MA70, but what I really liked was how much easier it was to tell how much RF growing room she has left without that head piece in the way. Considering we plan to use it to the limit, that is important to me. I don't expect to be able to use it FF given the low top harness slot on it and would prefer the other models for that, but I had to get what works best for us now, especially given it was so much less money. Since my DD is already 2 years old, I know going into it it won't last a long time, but we can probably resell it and it allows us to move our front seat back inches more than with the MA65 and that is priceless!
I just got it last week and it is hard to know how much you will like a seat until you really use it, but so far after using it on several outings I am liking it. We have the smokey pearl. It looks a little plain next to our daisy GN
, but it is very soft and I love the polka dots. DD likes it and slept soundly in it today. I hope this helps!