Nikon has hit another home run of affordable modern AF-S prime lenses. Combined the 28/1.8G, 50/1.8G and 85/1.8G made a great three lens prime kit. If you own the 85/1.8D I’d say it’s worth upgrading for the improved optical performance and smoother, quiet focus. If you own the 85/1.4D, it would be tempting to sell it and used the $400 difference towards another lens, flash, or a new body.
The only downside to the lens is the AF-C performance. Unfortunately it is not up to the same level as the 70-200/2.8G and other telephotos. But the focus tracking is much smoother with the 85G than the 85D's jerkiness. I still found the lens up to the task of capturing fast action indoor sports such as basketball and volleyball with Nikon's 51-pt and 39-pt AF systems on the FX bodies.