Stormscale Scion vs. Elemental Eruption

Which of these do you think is better? [[Elemental Eruption]] has been in the mtgo vintage cube in the past (but not the current version), and has overall been a pretty solid-if-not-incredible cube card. With [[Stormscale Scion]] being spoiled from the upcoming Tarkhir set and being very obviously similar, is there one that seems like it will be better? Eruption gives the dragons prowess, which is relevant, but enough Scions just all pump each other naturally, so that seems like it could be a wash. It might just come down to whether one being a sorcery vs one being a creature card matters - for instance if your cube runs stuff like [[Mizzix's Mastery]] then Eruption goes way up but if you have lots of bounce effects/things like [[Fear of Isolation]] in your cube then the fact that Scion has one "real" body instead of all being tokens will be relevant as well.

TD:DR - Obviously, as will all things cube, it depends. But what do you think will be better overall/fit into more cubes? Or is there space to run both alongside each other for redundancy, if you support the storm archetype.