R34 Coupe and Sedan

I see this coupe parked here quite often so I decided to park next to it. I had often thought about selling up my sedan and getting a coupe, however I was recently told that the sedan is pretty much just an extra pair of doors added onto the coupe.
I decided to research it and it turns out that the wheelbase (distance between front axle and rear axle) is the same for the two cars. I got some measurements from a Japanese website and found that the sedan is only 125mm longer than the coupe. Looking at them side-by-side, you can see that the extra length is from the extended boot of the sedan.

Theoretically they should have the same handling and characteristics, except that the extra doors add 50Kg onto the overall weight.
Either the sedan has no space in the rear seats, or the coupe has a lot of room in the back.
Happy weekend everyone.