I have about 4000 miles on mine and I’m completely stock. I’m looking into getting the Works drop in filter to lean out the AFR and then get the tune. Definitely picking up the Access Port too. I wish there was a reputable tuner in the 518 but from what I hear Ivey is the closest and one of the best. I do post on EvoM with the same screen name as here.
What dealer are you using locally? I use Mangino and they’re fairly forgiving when it comes to mods.