AlertOps is best suited for service delivery companies, as it tracks the whole process and create alerts if any ambiguity is there giving the time to respected personnel to resolve and manage the same issue to ensure the smooth processing. It even escalate alerts to different teams creating s consistent coordination between teams and saves a lot of time.
I recommend Splunk on-call is more suited where there are high incident queues; multiple teams need to be involved in handling a P1 severity issue. Multiple levels of escalation are needed environment where automated action is required. I recommend the solution for large-scale & medium-scale business units. For small-scale business units, I see the functional value is less.
VictorOps support has proven excellent for us. Because it is such a widely used tool, there is a lot of documentation on usage, and a large community of users to lean on. Also, many engineers have had experience working with VictorOps already, and the tool is so easy to setup / manage that much support isn't really necessary.
Although all the other products are also great but AlertOps has same and infact some better functionalities at less and better prices than other tools. AlertOps also offers free trail version which allows the users to take the demo and have a better understanding of the product which is not available in most of the other products available out there.
Splunk On-Call integrates better with our Splunk Cybersecurity and Reporting products due to the same family tree of the same eco system. We were previously using built-in on-call from individual applications and while adequate, they were difficult to manage and support SLA varied greatly across different applications. In addition we also used xMatters which did not integrate well with SAP products nor Citrix products so we were still using more than a single on-call product which was solved by implementing Splunk On-Call