A lot of products are now available on the market, and the battle is on the performance sphere. While for some of us, especially the travelers, we would like to minimize the number of cables necessary. Ideally, laptop + charging cables, and all other devices (mobiles phone, tablet, headphones, …) all charging with the same cable.
Waiting for good options with USB-C, actually mostly only valid for some ultrabooks, the best choice is probably Micro-USB.
It appears that the 2-in-1 tablets market doesn’t offer much Micro-USB products anymore, the 2 best ones being the Microsoft Surface 3, best in performances and smaller, 10.8″, or the ASUS Transformer T300 Chi, lighter and larger, 12.5″.