I have been running this website using Drupal 8.2 with PHP 7 for a couple of days now and i can safely say it is much faster, and without issues.
My primary worries wasn't so much running Drupal 8 with PHP 7 as i knew there wouldn't be any issues. It was mainly contrib modules. But i am glad contrib modules are working fine as well.
Without doing any website performance testing, you can already noticed the increase speed and responsiveness of the site. But if you want to see some benchmarks, i think this is a pretty good representation.
Furthermore, enable opcache (comes with PHP 7) and add memcache, the site becomes even faster.
So i think, this is a good time to start running Drupal 8 with PHP 7 to benefit from the increased performance and make Google like you more.
If you are in the midst of looking for a good web host to support and maintain your site, contact me to discuss. The benefit is that i offer multiple PHP versions (5.6 and 7.0) so if you encounter issues running with PHP 7 (not that you will :) ), you have the safety net of defaulting to PHP 5.6 with just a switch of a button.
In addition, i also offer free SSL as part of the plan to encrypt and secure your site.