I've recently installed a P-Series for a customer that has a Call Center to replace an S-Series with Queuemetrics. S-Series together with Queuemetrics was not very reliable and odd things happend all the time with no explanations behind it.
So far all is well with P-Series and is working nice however there is a complaint from the customer which is probably something easy for you to implement and it kinda makes a lot of sense:
In Queue Panel and Wallboard there is no way to view all the queues that an agent belongs to, I find that having agents that log in to multiple queues a very common thing and it is not practical for them to be changing the queues that they want to monitor all the time (this is something they were used to having on queuemetrics). They also want to have a TV in the callcenter room displaying a Wallboard with general perfomance of the call center but it only makes sense if they can see all the queues in one window, please add an option to view all queues both in wallboard and queue panel: