Another option is to look into retrofitting an 802.11ac card into your laptop.
Most laptop cards are standard mPCI-E and in most laptops in my experience they are relatively easily accessible. Obviously it's at your own risk but the reward is worth it if you don't mind poking about inside your machine. The cards (depending on what you buy) range anything from £15-50 - with an intel 7260-AC being around £20 these days.
I've upgraded a few of my own laptops over the years to keep up with wireless trends, even if the laptop only came with a single band card they've always worked fine on the 5GHz band in my experience. Probably not *as* well as if they'd been designed for it but it beats using an external adapter.
Don't attempt this unless you or a friend know what they're doing working inside a laptop though, not worth risking breaking things for faster wifi
It infuriates me how many laptops sold today *still* don't come with dual-band wireless, even business machines. Anything to save a few pennies on the BOM I guess!
Edited by summat (Sat 13-Feb-16 18:27:57)