Not worth the money, IMHO. The mounted light cav do have AP capabilities, IIRC, as they wield axes, but the archer unit is too small (36 on large setting) and don't offer any real advantage over the Noble Archers other than perhaps a range advantage (I certainly could be wrong on that account) as they use compound bows.

The Noble Archer is your best bet, I would say....good HA stats and can go to melee when necessary as they are more heavily armored than regular HA.

Just my 2cents........