Soft Roll-Top Tonneau Covers

I know this one has been beat to death, but I need help with finding a tonneau cover for my '05 CC w/ utili-track. I would like to know of any covers available that work with this system and the bed extender without any modifications. As of now, I am looking at the Truxedo Lo-Pro, and the Access Lorado. (I have heard that these need some form of modification.) If anyone knows of any pros or cons, or any other suggestions, PLEASE HELP!!! I am going nuts here and nobody is being very clear about options. Thanks.