I think
@rocketman122 might be a bit exaggerating when he mentions "ripoff". I got the Df when someone on Kijiji (our Canadian Craig's list) put an ad to exchange a D600 for a Df. For me, this was a way to get some money back for the D600 before it got too low.
At first, I was a bit deceived because it held so differently than the D600 and I wasn't used to the controls, but after a while, I can say that I really like it. The files are a bit smaller to work with and this doesn't bother me as I seldom print larger than 20x24. What I do like is the character of the sensor. I don't know what it is, but I find it has a different visual effect than my other cameras. Though I have to agree about the not so great focusing in low light, I love the low light quality it gets me.
Now, if the D750 had been out when I did this swap, I probably would have gone with the 750. But, now that I have it and I'm used to the different handling and button configuration, it's a sure keeper for me.
As much as Nikon is trying hard to sell their new models, I can say that I'm more than happy with my D700, D7000 and Df combination. I don't see why I should spend another penny for a different body. But I'm an amateur and if I was earning my living with a camera, I'd certainly be using a D810.
Now as far as the price drop goes, I'm not certain this still applies since the original post was made in december 2014. The price might have come down a bit, but I don't think it will drop any more. One thing I like about this model is that it's made in Japan where the 600, 610 and I think 750 are made somewhere else.