With Dinan parts comes the Dinan warranty. I would go that direction because our 335i is on its 2nd engine and wont stop throwing codes. We had a hard enough time with our BMW dealership to pay for the problem since we had the Active Autowerke chip, which to them is a big no no. So we ended up having to pay for the labor of installing the new motor, even though what happened to ours happened to a couple of 335i’s that i know of.