Having worked on multiple platforms, I can say that the only reason Groupcast was selected is because it's current capacity is one of the highest, however that system gets stressed during certain times of day, and wasn't designed with healthcare in mind. It will be missing many features that most consider basic.
Housecalls is antiquated with a Windows 3.1 esque interface.
Engage had the potential to set West up as a market leader. It was easy to program for, and everything about it was built in house, so there's less licensing to worry about. As for capacity, the system was very scalable given the appropriate resources...
In my opinion that program was sabotaged by upper management. The sale of Callpointe to West included a disclosure that the current server was flirting with capacity and would need to be upgraded within months. The then CEO actually did purchase a new server, but after her retirement the server was reallocated. West continued to migrate customers to the system, and things inevitably slowed down. Multiple requests were put in for upgrades, but we're declined due to budgetary restrictions. The fact that it's still running at all speaks to it's resiliency... It's been essentially running a 3 year long stress test.