Temporarily got my hands on a reasonably authentic Afghan shamshir with accompanying buckler about a month ago. Shamshir was oddly balanced, a little tip-heavy, with a pretty thick blade. Of course it's not quite clear where it lies on the scale between functional and decorative. But its edge was sharpened and I sure as hell wouldn't want to get hit with it. Buckler was the type with two grips and a knuckle pillow--it really forms an amazingly secure grip. I can see how that would be a preferred shield type in dueling, but in a mass melee I think I'd prefer something significantly larger.
As for the Greeks, I think the aspis is far too heavy to use effectively as a weapon. Perhaps if the stars align and your opponent isn't ready for it, you could edge punch him.