I know G lenses doesn't have aperture ring so wonder if for my purpose the D version are better.
I'd recommend against a "G" lens for this purpose since you'd need to rig something up to hold open the aperture control coupling lever while the lens is reversed.
I also recommend reversing an f/1.8 or f/2 instead of an f/1.4 not because of distortion, but because the slower primes have a slightly flatter field of focus. So if you want an f/1.4 lens for day-to-day use, consider buying a manual focus 50mm f/1.8 to reverse.
The D600 can control the aperture on a "D" lens, and in fact that's the default setting. When using a lens with an aperture ring on the D600 in this manner, you set the aperture ring to the minimum aperture; AF lenses have a switch or lever allowing you to lock the ring at this setting.
One of the biggest mistakes a photographer can make is to look at the real world and cling to the vain hope that next time his film will somehow bear a closer resemblance to it. - Galen Rowell