I recently aquired a 2nd BMW E39 540i car which are notorious for cooling system failures, typically being side caps leaking on raiators and expansion tanks due to the higher pressure system they run. I had replace the radiator on my first 540i with a Wizard cooling unit after reading up on the competitors units. I have a friend who owns another aftermarket all aluminum brand in his BMW, and has had nothing but problems due to the unit has epoxy in some areas rather than being built right and being brazed. This second car I purchased is being converted into a track car, so it is partially gutted and the clutch fan has been removed for track duty. It runs at nornal operating temperatures and has yet to show any signs of struggling to keep things cool. I am very pleased with both of units in both cars, hence the reason for purchasing the 2nd one from Wizard. Dropped right in, no modifications, works fantastic!! Thank you Wizard for making a great product!!