The Prowler Burst PDW is a bit unwieldy given that it operates as a five-round burst weapon — all that downtime between bursts is likely time you're being shot at.
But, if you can pair the Prowler Burst PDW with the Selectfire Receiver attachment, you're able to turn the Prowler into a fully automatic weapon. And that's especially meaningful with the Prowler, which fires heavy rounds (read: bigger, more painful bullets).
That said, this is a conditional weapon that you probably shouldn't grab unless you're either prepared for burst-based battles or already equipped with another weapon you can lean on until you find the proper attachment. Or if you've already got the necessary attachment, of course.