The Lunar Exalted have always been in the worst spot compared to the other Exalt types. In 1E, Lunars were safely regarded as the worst written of all the splatbooks, with the initial intention of never being playable only to be written without coherent themes in mind and then pigeonholed into a ravaging barbarian archetype. While 2E Lunars was certainly an improvement, that was certainly a bar that was low enough to trip on. In terms of their presentation they lacked a coherent place in the setting beyond sidekicks to Solars or else nebulous social engineers without any of the mechanics needed to actually bring this about. Their charmset was also awkward, and poorly put together.
3E offers a genuinely coherent vision for Lunars by starting with a simple idea of opposition to the Realm and its successors. They lack the passivity of 2E Lunars, who were unusually tolerant of a government that considers them enemies that must be purged on sight. However, they are not pigeonholed as rampaging destroyers of 1E, either. They have a charm set that's far better equipped towards shaping and building societies, as well as elements of tricksters and manipulators that go into far more depth than prior editions. The Lunar power set is flexible, creative, and thematically evocative. The art in the book is, compared to 3E's core, far more consistent in quality along with some fairly briliant pieces in place, and the setting fluff gives Lunars a far stronger role in a setting.
Even if 3E is not your preference, I do recommend this book to Exalted fans, both to finally give Lunars a coherent place in the setting as well as have examples of powers and abilities that are both effective and interesting. This is a definite improvement compared to poor showings from prior editions, and after the stellar showing that the Dragonblooded also benefitted from I am very eager to see how future splats and archetypes develop.