What can I say? $1000 is about where I personally stopped being able to hear a difference. Its a completely subjective, Rule of thumb. The value of money is constantly changing as is the value of good (Is the 950 a $500 processor (used) , $700 (new) , $1000 (3 years ago) (what was the rate of inflation over the last 3 years?)
$1000 just seems to me to be about where you need to be to be guaranteed of getting into that "pretty good" system area. Are there devices below $1000 that might get you there... maybe. Is the 950 one of them. Probably.

All I can say definitively is that;
1) there is a Price/Performance Curve and in my experience this curve is NOT linear, and it is certainly NOT flat.
2) Separates in my experience sound better than integrated solutions
3) A device designed as a standalone Preamp will, in my experience, sound better than a Integrated Solution being used as a pre-amp.

If I had to guess as to why this may be true (in my experience), it would be the combination of Higher Noise components (amps, even if they are not driven, still amplify whatever noise is there, and transmit it to some degree back via the power supply or through induction) with Low voltage signal paths

I don't think $1000 is some sort of magic number and that the 990 is going to be worlds different from the 950, or maybe even a receiver at the same price level(If I buy a 990, it won't be because I think the sound is so much better than a 950) Sound differences (if any) in the 990 will be due to those factors I mentioned before (new design, new DACs etc)

Some people may be able to clearly hear the difference between a $1000 device and a $5000 device in a blind test. Having never done one, I can tell you right now, I can't. Consequently, I will never spend the money on a more expensive solution.