Well there was this one Polybian Hastati unit that held an elite Epeirote phalanx (can't remember exact name) for quite some time. I was damn proud of those buggers. They didn't break or even waver for almost 10 min while my army chewed on the other elite phalanxes there before finally getting to that one. By the end they were down to 10 men, but they held, dammit! I believe in that campaign they are in Nubia or so, finishing off the Ptolemaic remnants there (yes I did retrain them), though it is now the Marians so all losses now are permanent.
And I also have this thing for Numidian Skirmishers and Numidian Skirmisher Cav now, after a full stack of em (12 inf, 7 cav, 1 gen) held off countless Ptolemaic incursions, using auto-calc no less. And even against elite armies with nothing but elite phalanxes and galatian heavies.