Thanks GPF
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Kraut meister, that piece is a Y because it appears that the hose orientation is better suited for it. You can kind of see what I mean from the pics. Putting in a T just means the hose coming up from the main coolant hose connected to the radiator has to take a slight bend to it. It doesn't even kink the hose.
On flow though, I did notice that stupid plastic t had really small orifices, almost like it was meant to restrict flow. The brass T I had bought had slightly larger openings. However, from the pics, it would appear the connections from the heads also have small openings and hence would be restricting flow anyway. I went ahead and fitted mine and as reported from a similar fix in 2013 on my N62, have no long term problems to report. The fix on my X650i with the N63 is going well. No more smell of leaking/burning coolant, temps are good and levels are fine!