Not at all. We have used Vivo V5s during our reviews and found that despite using for longer hours, we did not encounter any heating issues.
Yes, you can play FM Radio on Vivo V5s.
Yes, you can use Jio 4g sim card in this phone.
Vivo V5s comes with latest Android 6.0 Marshmallow OS which has got Vivo's patented FunTouch 3.0 skin layer. Since the device is newly launched, we do not expect that company will release the new software update immediately.