I'm in the same boat. I was leaning towards the new Surface Pro because my wife has a Surface Pro 4 and really likes it. But it's small has some limitations compared to a "real laptop/tablet" like the Spectre x360. I'm pretty sure I saw somewhere that someone was using the HP Thunderbolt dock with a Spectre x360-13, but not sure about the 15". I do wish that HP would simply state what docks, if any, are compatible with the Specte x360 products. Please post back here if you learn more, and I'll do the same.