Maybe same style but they are different.
DX12: Carburetor : 3 Needles Slide 5.4 mm
D3R: Carburetor : 3 Needles Slide 5.5 mm
D5R: Carburetor : 3 Needles Slide 6.5 mm
From what I read earlier in this thread the larger D5R carb makes it harder to tune. My D3R tunes pretty easy. If I have issues when I use get around to using the D5R I'll just use the D3R carb I guess