Bike Forums - Differnce between a 2001 Klein Quantum, Quantum II, Quantum Race

I have been doing some basic insight readings for Klein bikes as well, why not!?!

The Quantum bike series is of serious interest with it being a road bike and all. I do have some questions that maybe another Klein enthusiast may clear up for me.

First: Is the Gradient Tubing considered a "better" option for the bikes? The bikes with Gradient tubing were made via Trek and not made in the Washington Factory where Klein had a production line of about 200 workers. With many vintage items, there is the whole aspect of owning the "originals" of whatever. But the Gradient Tubing, where I believe they further thinned the walls of the aluminum where they could and strengthened the tubes by butting them at weak points is apparent. Not only this but the fatigue life is apparently much greater in the Gradient tubing. Really what I'm getting at is, are Trek built Kleins really that bad? or is it more of the collectors nostalgia that makes the Washington built Kleins better?

Second: What are the differences between the Quantum series? some frames are labeled Quantum, Quantum II and Quantum Race. Are the frames themselves different in structure or geometry? or at the time were the frames labeled according to the component package offered? as in There is no difference between a Quantum Race and regular Quantum frame, just the component package offered at the time of sale?

Thank you all for the help and time taken
Best