I got the non-extended cargo mat for my '07 Suburban and the fit is absolutely perfect. There are no gaps or bunching. Remember there are two types of Weathertech cargo liners available for an '07 Suburban/Yukon XL/Caddilac, etc.: 1) is the non-extended version that butts right up to the back of the third row seats; and 2) the longer version whereby the liner extends underneath the third row seats, requiring the user to modify (cut) the liner if the third row seats are used.
As I will rarely, if ever remove or fold up my third row, I'm using the non-extended version. I just didn't like the idea of having to cut my liner, not for the difficulty of the job, but if an accident did happen and perhaps some milk spilt, I didn't want it to get through the holes and under the liner.
As stated previously, fitment is perfect and the material does not exhibit a "cheap" look or feel.
Also note that I have the auto lift rear gate. Not sure this changes anything or not, but I wanted to throw that info out just in case.
I will reveiw the full interior set of Weathertech's when they arrive later this week!