I've only beaten him once using Zanmato. However, I do think I have the stats to beat him - every stat maxed out except for magic and luck (being 220-ish) for Tidus, Wakka, Auron, Yuna and Rikku.

I kinda quit while customizing new armours though, that stuff takes long. But I might try again soon, I do kinda feel like playing X.