Auto-Rx vs. Schaeffers Neutra 131

Hey there, As many of you may have read my other posts, I am interested in doing a changeover in a 2003 Saturn VUE from Dino -> Synthetics. I have seen many praises for the Auto-Rx and have heard a mention of Schaeffers Neutra 131 as well. I would like to do a cleansing but, I do not know how much time I will have before I get sent off somewhere else [Patriot] . The Schaeffers was shown to be a good pre-500-mile prep before doing the rinse of oil and adding in the synthetics. Has anyone done this and had good results. We have had the Saturn since March 03, and has 12,800 miles. This vehicle is the wife's and anything I can do to make the things run better in North Dakota weather would be great. Any suggestions ?? Thanks in advance for any input Slade