I beat Dot Hack Infection, Mutation, Outbreak, and Quarantine in order back when they were first releasing on the PS2 in the US. And importing my memory card save every time.
My friend witnessed me defeat the final boss in Quarantine. It was such a long and crazy fight. And the whole thing was just mindblowing.
Sadly I don't have any pictures or videos of it. And I traded in my PS2 a long time ago.
I have been considering revisiting the game but it's a big game with ALOT of content. I don't know when I'll get around to it.