The triple Black does make it harder to cast in Limited than you might think, especially on curve 5 mana reanimation spells normally don't fair well in Limited, they are usually in the D range, even with some extra value tacked on, but I think this one will overperform
However, although this card fell by about $100 from its previous high of $480, Giratina still stands strong, partly due to the incredible mosaic-like artwork this card boasts
Im a big fan of both cards
its simple, instantly recognizable, and universally playable
For example, you could have 4 copies of Charizard and 4 copies of Dark Charizard in a deck (assuming the card was in Rotation), as Dark Charizard evolves from Dark Charmeleon instead of regular Charmeleon