The downside is still a Goblin Electromancer that occasionally pings you for damage, but the upside is flipping this planeswalker into Ral, Leyline Prodigy, a fairly tame walker that preserves the front side's cost reduction and adds in some other forms of disruption
But my position comes with a cost
Plenty of decks rely on a single big threat, whether its Troll of Khazad-dm or Tolarian Terror
Every so often, a card comes along that really looks underwhelming but makes a major impact
Norn's Annex is one of the more powerful reprints, worth around $5
As such, the strength of these cards is already known, and many of the cards included are staples across multiple formats