Pros of PMP is that you get control and more audience targeting which can better drive value for the brand. In general, driving performance goals like CPA means you need to target the right audience wherever they are found (inventory wise). And being able to control levers like frequency, device type, sites, etc is very valuable to drive that efficiency especially if you have multiple inventory sources.

Pros of PG is usually you get first look and lower rates because you are giving up control and will let the pubs sell you anything and everything. If you go this route, I’d highly recommend running the PG thru an objective DSP that way you can at least report out on what is actually happening.