I installed Hola as a Chrome extension some time ago (within the past year) when I first heard about it from someone who is less technologically inclined than I am asking me if it was safe to use. (In fact, I still have it installed (disabled) as I write this--something I'll fix right away!) It seemed to do what it said, but I also didn't like the idea that all the traffic was being routed through who knows where.
I said that it looked like it was probably safe to use if you really needed to, but I recommended to always disable the extension when she didn't need the VPN features so that she could be sure it wasn't "spying" on her (gathering her information or using her services) in any way.
Looks like I was right to do that.
Thanks for sharing this.