Guys longsword, greatsword or dual swords?
dual swords -- fastest weapon, highest average dps potential, lowest range, loses sharpness the fastest. you're constantly in on the action.
longsword -- second fastest, second highest average dps potential, range is 2-3x that of dual, loses sharpness relatively quickly. plays something in between dual and great
greatsword -- slowest weapon (i mean geological timescale slow), lowest average dps potential (still very good if you constantly land your charge attack), highest single attack damage, same range as long, keeps sharpness the best. can block (this stuff saves lives man). much more of a hit and run weapon in most cases.
i personally like greatswords the best because the other two always make me feel like i'm cutting through paper
really though, they're all very good options and you can't go wrong by trying them out. hell, main all three.