Don't Install iOS 10.2 If You're Worried About Problems
If you're having an excellent experience on iOS 10.1.1 or below, and iOS 10.2 fails to excite you, consider holding out.
iOS 10.2 users are complaining about Wi-Fi issues, various issues with Bluetooth, activation issues, problems with various third-party applications, installation problems, UI lag, random reboots, and severe battery drain issues. That's just the tip of the iceberg.
If you're feeling comfortable with your current version of iOS you might think about waiting for the next versions of iOS 10 to arrive. iOS 10.2.1 is in beta and an iOS 10.3 update beta is rumored for January.
Remember, there is no way to downgrade to iOS 10.1 or iOS 9 so you'll want to be sure about your move to iOS 10.2. Once you make the move to iOS 10.2, you're stuck until Apple rolls out a new update.
It's unclear when Apple plans to release its next bug fix update but it could be a few weeks before we see something new.