Night blue metallic from Porsche is much closer to BMW tanzanite. Gentian has much more purple in it, similar to bmw interlagos blue back in the day.I am such a huge fan of darker blue, that I am surprised Gentian Blue was not for me. It would have been if it wasn't for that BMW in Tanzanite Blue sitting right next to it. I will need to post a photo of the two side by side for the group to see. I have to say those wheels are what makes me love this vehicle. So glad I sprung for those.