I used Whisk. The model listing shows 3/4 because testing against Imagen 4 did not result in a measurable increase in accuracy from Imagen 3.

https://labs.google/fx/tools/whisk

Well they've labelled it 3/4 so I'm guessing they can't but you can use 4 it in whisk

Tell me you’re using Imagen 3 without telling me you’re using Imagen 4… or something