If you have a lot of notifications then YES. Notifications are significantly less irritating and substantially easier to work with and manage. Otherwise iOS 12 feels mostly like a polished version of iOS 11.
- Notifications are substantially easier to manage, particularly from apps with large numbers of notifications (Instagram, ToDoist, GMail etc.).
- There have been a few niggles, but to be honest I think there have been fewer niggles with the iOS 12 beta than with the shipping versions of iOS 11. If in doubt, restart (which was true for iOS 11, iOS 10, etc.)
- Lock Screen widgets – seem to be much faster and much more responsive
- Control Center – Am not that enthusiastic about Apple moving the swipe starting point for the Control Centre gesture on the iPad.
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Disclaimer/Reminder: back up your iDevice and archive the backup so you can do a restore if anything goes wrong. Hasn’t gone catastrophically wrong for me (yet) but YMMV.