I have been an avid 40k player for the last 6 years. I've tried to purchase AoS armies countless times, along with data cards, kits, battletomes, etc. and nothing really ever stuck with me. I just picked up the CoS battletome two weeks ago, and since then I've built over 1000 points of converted CoS models, bought another 1000 models, and have my own backstory and theme. It's the only book that has actively inspired me to actually get into AoS for real!