i have the 400R. i like the case and it's easy to build in especially with the side panels that flare out. compared to the 300R, the 400R has a larger HDD cage, one more fan, and rubber grommets. the lack of one fan could be a good thing since I personally don't care for the corsair fans. they are loud and I replaced all my fans with scythe & enermax tb silence fans.
all the cases you selected are solid, make sure you get one with looks that appeal to you since you will be staring at it for a while.