Hi folks. Southern Ontario with GM 3800 V6. Looking at each of these oils. FYI, car will be outside all winter but will be using an oil pan heater which works VERY well even at -21F. My go to oil for summer is the GTX High Mileage (which is semi-syn). With the Edge being 'Full Syn', does it really matter? OCIs will range between 4k and 5k. Thanks for any ideas/discussion.