By chance, I went to a streaming demo at my local store last weekend. They had the Naim HDX and the Olive 06 and 04. Firstly, I'm afraid, the 06 is way ahead of the 04 in sound quality, greater detail and bigger sound stage. The Naim HDX was comparable to the 06.
It is difficult to compare as they were in different rooms, the 06 a Krell Kef blade set up, the Naim, a naim electronics and Sonus Faber stand system.
I would put both at a comparable level to my Leema Antilla, a good player in the £2500 price level, so neither of the straming solutions seem to challenge very good quality CD players, yet. The retailer rapidly configured an Ipad to control the olive.
On both systems, Hi res, 24/96 I believe, clearly beat standard CD quality and a big plus, was the quality of some of the better internet radio channels.
So I would say from this demo only, streaming is not yet matching top CD quality, but that is my only exposure, so there may well be better.