CCM is no longer supported so ultimately ACD functionality will converge to Solidus (I believe there will be a Lite version). Offcourse Solidus is targeted at contact centers but for smaller customers there are also advantages:
ERP/CRM integration, better reporting, IVR functionality, any extension can be an agent, etc...
Ultimately, it all depends what you really need;
if you are happy with your current ACD/CCM setup and really have no extra needs, keep it that way...
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