I have recently bought LG K10 smartphone along with which jio sim was provided to me.I was rally excited as I was about jio sim. The person at the mobile store told me that my sim will get activated in 2-3 days after which I can use the data and voice calling services of reliance jio. But it actually took around 8-10 days for the sim to get activated. Even after being activated the signals did not came for a day. Also the customer center will never pick up your call. Then finally after a day signals started comming. Now I have been using jio for a week. The internet speed is good, but its voice calling is pathetic. The network always shows busy for every other sim apart from jio. Also the voice quality is also not satisfactory. So I would say it is a good option for internet but not for calling.