Since I just recieved my new SMD Lunar Duo I have been reverently petting and feeling it.

I noticed that the floor material is very tender, and had read that I will need to instigate more stealth camping in order to protect it for the future.
I am now understanding why ground cloths are being used. With my older climbing tents, and even with my Kiva, I was able to get away with either no ground cloth, or in the case of my Kiva, some of the "heavier" space blankets. But the Kiva is mainly for larger groups, so now I'm wondering what is a good material to use for my LD bottom?
I see that SMD sells a "hard tyvek" sheet, and it weighs 6oz! I'm not thrilled with tyvek, nor with the extra weight! but my only contact with it is as a building material that I fight as I work! LOL... is this the same basic material I cut up on homes? I can see it being slippery, noisy, and picking up all manner of debris.... so whats the alternative?