Comparing the Zweihander and the Greatsword

I was taking a quick look at the Greatswords that I had and I noticed something: Both the Greatsword and the Zweihander have the same base damage stats, even if you upgrade them, but the Greatsword have higher Str requirements (the Zweihander needs 24 str and the Greatsword needs 28 str).

So... is there ANY advantage in using the Greatsword? The Zweihander have the same basic attack and the strong attack of the Zweihander, in my opinion, is a litlle better. Besides, you can use it early in the game (just run to the cemitery and take it).

So... is there any difference besides the strong attack of the Greatsword?