I still think EK has the better offering here. You can even upgrade using miles when you're on board, if you don't like your companion (subject to having at least Silver status with EK).
It's handy because you can assess the cabin before having to make your decision. You don't upgrade from Y before you get to the airport, use a load of miles, and then see that you could have had 4 Y seats to yourself if you'd stayed where you were.
It also rarely matters if there's award availability, either. If there's a seat in F and you have status, chances are the purser will process the upgrade.
It's the one big thing I'd like BA to change.