Just a quick update.
Received the card on Monday, delivered the PC Tuesday. I had little time to compare it and test, but I must say that I was pleasantly surprised. On the limited tests I ran, it gave my 270x PCs+ a fierce fight.
Will report later with some numbers, but in a quick summary the GTX950 is almost 270x performance at a lower price and furthermore, good availability, something that cannot be said anymore of the 270X, specially not close to the $120-$130 mark that the GTX950 is popping up.
On a side rant, it is beyond me why somebody at AMD (product manager?) decided that the R7 300 series was to be "pro" chips. The GPUs are so mature that there should be literally no rejects from the full blown "XT" parts...