I started using it when we were still in testing phase of our product development lifecycle (PDLC).
It was one of first tools used by the team during this time as they had heard good things about them from others who have worked before us at different companies/organizations. We also realized some benefits right away but there really wasn't much else out yet so didn't stick around too long either way! Once more features came along later down the road i would say just keep your eyes open - you never know what might be coming up next or how someone has done something similar already. As mentioned above though early use did see most benefit here since everything could run via API which allowed easy integration into other systems such as JIRA etc..