I see you guys discovered BMS has expanded their DPFIX to include M3 models. It's a different product than the N54 DPFIX but has been tested in a few cars and is working very well so far. You also get full readiness! Install looks more complicated than it really is. I can install one in around 10 minutes on the M3 as the DME is a little easier to access than 335 models. It's not for use on pollution controlled vehicles of course but for race cars and those out of country this is a great way to go if you don't want or are not allowed to use a tune but need to get rid of that annoying dash warning system.