I've run a small ISP before so this isn't my first experience with TP-Link and they all work great. This product is no exception.
I'm using this as the antenna on one side of a wireless bridge within my home. It replaced a omnidirectional antenna that was also rated at 9dbi.
The signal runs through like four walls across the length of my house and improved about 10dB.
Also I noted that when I scanned for access points I was now only picking up 10% of the amount with the omni antenna. This is good as it indicates less susceptibility to security risks as the signal is now directional.
Overall: TP-Link provides a great value when it comes to networking gear and I've got a lot of it(five routers, four switches, many antennas(parabolic 24dBi, omni 15dBi,etc).
This is the perfect antenna to improve your home network especially if your router is on one end of your home.
It offers a 60 degree angle of signal projection which is perfect for strong signal strength over short distances or when bridging point to multi-point over mid range(less than a mile).
If you are creating a point to point bridge past 100 feet I'd recommend something that focuses the signal more such as the 14 or 24 dBi antennas.