I agree with Dfive.
If size and weight are your concern, then u should have gone with the 50mm f1.8G (or even the 50mm f1.8D). By choosing the 50mm f1.8G over the 50mm f1.4G, u shave off a third of the weight (185g vs 278g) for half the price (ard S$250 vs ard $500). That 1/3 stop more u can get with the 50mm f1.4G is negated by the fact that u also have a Sigma 50mm f1.4 ART lens that u can use if really need be. It almost becomes a 85mm f1.8G vs 85mm f1.4G comparison where for a lot more money, u get a bit better optics in return. Not image quality, but maybe just a bit more bokeh at the background, the difference being hardly noticeable by 95% of those who view ur shots.
I believe that the reason y Dfive deems this lens as a rubbish lens is not because it can't perform, but more like it has no selling point. Lightweight? Nikon's own 50mm f1.8G and f1.8D triumph it. Sharpness and bokeh quality? Sigma f1.4 ART triumphs it. In this case the Nikon 50mm f1.4G is basically sitting in no-man's land, just waiting for Nikon to refresh this lens.
But well, since u already bought it, no need to go through the buyer's remorse.

In the end, a lens is still a lens, the final image is only as good as the photographer, not the equipment.

So enjoy your new lens