I have the standard GM roof rack and Thule racks and there are several options with Thule. You can get bike racks that mount directly onto the stock cross members. I didn't like this options because the stock members are a little on the thin side for me and they do not slide around easily. Also, with this option, the bike rack will mount to the stock cross pieces with a plastic mount that is more universal and not specifically designed for any particular car. The second option with Thule is to get a foot kit that mounts right into the stock bars that are screwed into the roof. You then get Thule bars for your cross members. Pretty nice and a good fit. I also did not go with this because it mounts the Thule cross bars very high. It's hard enough to try to get a bike on the roof. The third Thule option is a kit called the Rapid Rail. These are one piece cross members with attachments to mount to the stock roof bars. They essentially have a clamp that when cranked, grabs the stock roof bars like a vice grip and locks. It has rubber padding not to mark up the stock bar. It is very low profile and does not interfere with a sunroof if you have one. Easily removable and you can mount any Thule item since you are using Thule cross bars. With this setup, I have 2 Big Mouth mountain bike racks and a Play Pen basket for cargo. I can easily change between them. I have received a number of compliments about the versiltility and actually the looks of the setup.