Just wanted to clear up one thing, aluminum is not aluminum. It's aluminum alloy and every manufacturer uses different aluminum alloys. It's the whole competition of who has the best alloy to make the most efficient and durable engine.
I am pretty sure that there are many that are similar, but none that are identical.

I use whatever Mercedes recommends. It might be a little more expensive, but I know that I am getting the best. Plus, I've seen it too many times people buying aftermarket parts just to turn around and buy Mercedes original because of poor performance.

Vin