I like that they are very flexible with their scheduling options, allowing you to set up everything from recurring meetings through reminders via email or text message (SMS).
They also have an option for audio conferencing which is great because it allows me see everyone in my office while we're all talking at once! The system has been glitchy over our last few years of use so there's always something going wrong when trying new features but overall this service gets us where every need comes together quickly without having too many people involved - especially if its just 1 person managing your schedule needs as opposed to multiple team members who each may want different things out of theirs own schedules/schedules being managed by others etc.. We've used them since day one back before Slack was even released into production yet still haven't found anything really bad about MeetNumber other.