I have a collection of BMW M cars, from NA S14/S54/S62/S65/S85 and my wife drives a tunes E70 X5M with the S63 Twin Turbo engine. In all of my vehicles I am extremely particular about the fuel I use however even the best stations (Generally National BP and Chevron Stations) I will often register the DME fuel quality as average in addition to a reduction in performance and also pre detonation. With a bottle of the 108 with 93, the DME that have fuel quality sensors change to excellent. If I omit a bottle it returns back.Fuel economy on the Turbo BMW engines is consistently 10% higher with this in the tank on long trips. I keep a spare bottle in the trunk (note in Texas summers the bottle will expand and possibly explode) and when we make long journeys back for the Holidays I bring multiple bottles in the event we only locate a garbage local gas station with 91 that is likely filled with additional garabge.I am 100 percent confident in my use cases, especially the high revving NA V10 M5/M6 , this is worth every penny if you buy a case. At 4 dollars a bottle it would easily cover converting regular unleaded to 93 and pay for itself (especially in large cities with inflated gas prices).I rotate this in and out with Liquimoly products and all of my cars run like a champ despite the high temps in Texas. Highly recommend for all applications. I do all of my own work, build BMW engines and tune them on the side for additional income. I was not paid in anyway for this endorsement.