Not a bad package but I suspect the Win8 aspect is mostly hype and only a question of having drivers available. Likely it's using non-custom third-party interface and radio chips (RealTek, Atheros, etc.)
In a world where 11.ac is going to be adopted in phones and tablets pretty soon it would be pretty silly to invest in an expensive aftermarket atachment that does not support it. It is silly already that something 'so much better' than onboard would not even support 5GHz. Yes, range is gained through 2.4GHz, and if that is all they are going for then maybe the compromise is acceptable, but without 5GHz it makes this only useful for low traffic networks or places with nice clean spectrum available. You ran transmit and receive 300mbps all day, but if there are a lot of devices in the area then even a bad 5GHz connection will be a lot faster due to the lack of drops.
I purchased this for my Lenovo Helix. Some comments on here I thought I would clear up.
First, there are no drivers available for windows 7. It does not work on my windows 7 laptop. It is plug and play as they advertise on my Windows 8 Pro Tablet.
Next, Performance did see a marked improvement. Speed was faster according to several metrics when testing at home, and I was able to see 4x as many signals around me as I could before.
Lastly, on it only being B, G, N. This isn't meant for use at home or office. If you are in those locations and using a 5Ghz connection there are other solutions that are better for getting performance boosts, that should be focused on the AP. This is for when you are travelling, RV parks, Hotels, Airports, Coffee Shops. Places where there are often AP's that are down or for those that you have accounts to like Boingo, are too low to really use. Those folks won't be upgrading their equipment to 802.11ac anytime soon.
For 60 bucks this thing is a solid deal for what it provides. A sizable boost in range and power for public wifi hotspots.