Awesome thread. I'm been going back and forth between picking up a Magnetic and Oxford white '18. Looking at all your pics has me leaning towards the Magnetic, ha!
If it's a weekend cruiser I'd keep the GT500 (i have an '11 GT500 as well). I'm actually working on adding an '18 GT as a DD. I'm gonna go with a manual though, as I think I'd get bored with the automatic fairly quickly.