Complex sentence: Prior to the existence of the RFSU's, coastal surveillance in the remote north was carried out by the Australian Special Air Service Regiment, whose primary role as reconnaissance and surveillance soldiers made them ideally suited to the task.
Split into simpler sentences: Prior to the existence of the RFSU's, coastal surveillance in the remote north was carried out by the Special Air Service Regiment. The SASR's primary specialty as reconnaissance and surveillance soldiers made them ideally suited to the task.