Board Thread:General Discussion/@comment-26044650-20150227025814/@comment-25889587-20150227031412

25 S-rank treasures = You HAVE to expand your treasure cabinet, one way or another, so right now it's either buying with 30 crystals and do the works, or pay for 119 crystals.

But seriously though. If Devsisters did not ease up the treasure cabinet upgrade, and still goes for 100 Crystals, then I guess it doesn't matter if you buy him with crystals.