Yeah they are definitely good. Expensive but good... but that shouldn't stop you from running them. They are super versatile, fast and ultra-maneuverable with their thrust moves. If you can't decide between Hawks or Spiders for CW allies, Shadow Spectres are essentially both with higher strength weaponry. Great utility unit for DE that can help get extra anti-tank into your force, and when taken alongside WWP Archon, Scourges etc it gives you a lot of deepstriking opportunities.
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