After applying Cisco recommended QoS configuration to a WAN site router users experienced performance issues. The problem was resolved by changing the default queuing to WFQ - from WRED/FIFO. The Cisco documentation recommended FIFO/WRED for default traffic on a medium size WAN link >768Kb<2048Kb. REF:"Enterprise QoS Solution Reference Network Design Guide v3.3" PG 3-10.
Is it best to use WRED/WFQ rather than WRED/FIFO?