Loads of us have. If you want to completely bypass Guadalajara, it's money well spent. It's about the first off ramp past Tequila, and in June wasn't well marked. Recently someone took it and said it was very clearly marked as Macrolibramiento Guadalajara.
Do a quick search on this site and you'll get all of the details. There are other bypasses that are also quite wonderful. Again, check for them.
