Advantage of Active/Active over Active/Standy F5 pair

An active-active architecture can be helpful in case of high load over an active-standby architecture. With the drawback that, if you loose one of your nodes, the other one will not be able to cope with complete traffic load.

Most of the time an active-active solution makes sense in a (at least) 3 node cluster where one is on standby, in case of a loss... planned or not (e.g.: maintenance)