Rob, you have misunderstood.
- The 5100AGN is in the Vaio Z. That machine is six years old.
- I own an Intel 7260AC which I specifically purchased for a NUC D54250WYK (about a month old).
My comparison mentioned earlier was that the Vaio (with its 5100AGN) gives speeds of 54Mbps whereas the NUC (with the 7260AC) struggles with 256Kbps, assuming it remains connected. This, despite the fact that my network is uncongested and the fact that both machines are in the same position. The test was done with one machine turned off when testing the other. I have no plans on using the 7260AC with the laptop; that's not why I bought said card in the first place.
I cannot begin to describe the frustration with the speeds that the 7260 is giving me. Whilst it is reassuring that Intel is rolling drivers, it's (extremely) disappointing that the issue remains unresolved.