I like that it allows me (as an API consumer) as well, so not just my own website but other people's sites too! The interface is great for both consumers of our services AND providers themselves - very nice indeed!! It can be expensive in terms with licenses etc., however this isn't something we've found difficult or had any problems managing at all yet :) For us specifically there are two things which have been helpful using assertable; firstly being able see what kind/severity level each failed assertion was given when reporting back from customers through their tickets system has really helped drive down complaints about issues where they're unsure if its them vs code / api provider faulting out instead :). Secondly having some visibility into how many times certain endpoints were called per month helps give you insight around your usage patterns without needing manual data collection methods such as Google Analytics!