Actually, the one state that has had the most success in cutting down on meth labs is Oregon, which has a prescription only law. It's not meth use, but the meth labs that are the real problem here, and unless we legalize meth, going to prescription-only for Sudafed is the best option available to rid ourselves of the toxic waste dumps known as meth labs.
Oregon has seen more meth labs and drug abuse since the prescription requirement was enacted.
Do either of you have a credible statistical source to back your claims here? Unless you do, you're just going to argue back and forth.
http://www.oregondec.org/OregonMethLabStats.pdf (Original link had data 2003-2008, revised link adds 2009 data.)
It doesn't speak to meth use, since meth can be imported from other States where it is easier to manufacture, but meth lab incidents in Oregon have gone from averaging 40 a month when there were no restrictions to 20 a month once they required a picture ID to 10 a month once they starting logging those purchases to less than 2 a month since they have been requiring prescriptions. While restricting Sudafed likely has a minimal effect on meth use, it has a very demonstrable effect on having to clean up after the toxic waste dumps that meth labs are.