Reviewers largely see Calendly as a reliable, easy scheduling tool that saves time by replacing back-and-forth emails with simple booking links. They repeatedly praise its calendar and Zoom integrations, usefulness across client calls, consulting, and global time zones, and say it works well for everyday meeting booking. The main complaints are limited flexibility for more complex setups: defined bookable time blocks can be awkward, some features feel restricted or unintuitive, customization is incomplete, notifications could improve, and a few users mention booking-link editing and occasional conflict issues.