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SuperFi 5 back in 2009 when it was still branded as a UE product, and got myself the UE600 this year, which was supposed to be identical.
This two has nothing in common at all. Superfi5 is dual driver. UE600 - single.
He's referring to the Super.Fi 5, not the Super.Fi 5 Pro (which was indeed a dual-driver BA in-ear with kind of "Triple.Fi 10-shaped" bodies).
The regular Super.Fi 5 was a top-firing single-BA in-ear with the same body shape as its successor, the UE600. I don't know if there are any tuning changes (dampers, impedance), but the connector has changed (angled vs. the previous straight one) and of course the packaging.
The regular Super.Fi 5 gets overlooked way too often.