GKnot basically started out life as a bitrate calculator. It is opensource so anyone can update it. AutoGK on the other hand is closed source and the developer isn't adding new features, just bug fixes mainly now. If you are happy with AutoGK's output, then I see no reason really to go further. For some people it is all about the encoding process though, not about watching the final product. I tend to avoid guides, so I really can't offer anyway. Plenty of info around if you are willing to spend the time to look.
No new features, but at least AutoGK is updated as I said. (GordianKnot has not changed since 2004.) From len0x, March 12, 2006: "Version 2.27 is out - Didn't want the last version of AutoGK to be remembered as the one throwing errors on startup when used with some version of DivX, so here is an update." There is a changelog of new components and compatibility fixes... One of them is 'fixed compatibility with DivX 6.1.x' Does this mean GKnot is not compatible? Who knows? I use XviD, LoL (it works great :^) Point is, the AutoGK is actually newer and more current than GKnot - right?
Sounds good to me. However, I was just trumped with killer news. My buddy got me a full copy of the new version AVS Media SUite 5. It's unbelievable. Perfect copys of DVD originals. I almost crapped myself.