The super heavy cav will roll over chariots in a head on charge.

Also, I did some MP testing of the Molloson Agema and they are possibly THE best cav of the heavy cav/non cataphract class since they trade armor for pure defense. The most effective cav based anti-cav weapons are the charging lances(since it attacks so fast, has high lethality, AFAIK a mount bonus, and is AP but mostly the AP). But MA have hgih defense isntead of armor so they actually get a defensive advantage over say... Companions.

You can try it, they beat Companions head on.