I like that it's easy for end-users, as well as administrators of booking systems/integrations (such as ours), because there are many different ways that one can be set up; however, this also makes configuring things more complicated at times! We use WCPB in conjunction with our own internal system so we don't have any issues from integration side but sometimes when an admin changes something they forget about how their users will see them - which causes confusion or misunderstanding between both parties.
This software allows us flexibility over what type of bookings go through our website without having too much manual inputting required by staff members who may not understand some aspects such as tax rates etc.