Of the 20 or so varieties I've tasted, the ones in the Mysore subgroup (Mysore, Pisang Ceylon, Pisang Klotek) are my favorites. Incredibly sweet-tart, fruity flavor. They have much more acidity than any of the others that have been mentioned so far. Their biggest down side is that the fruit are small -- smaller than Manzano.
FYI, Golden Pillow is in the same subgroup as Manzano, the Silk subgroup, definitely not the same thing as Goldfinger. Goldfinger has a peel thickness on par with Cavendish from the supermarket and similar size fruit. Golden Pillow should have a thin peel and similar size as Manzano/Silk Fig etc. Golden Pillow is described as being similar to Manzano but without the horrible astringency when not fully ripe, but I haven't been fortunate enough to try it yet. Sounds like a winner.