I'll be honest - I'm a huge fan of Sarah's, but ACOTAR just didn't do it for me. My main issue was the relationship between Tamlin and Feyre. Tamlin wasn't worth everything she went through to free him, and the amount of effort she put into freeing him (she could've died! more than once!) just didn't feel right to me. 
 HOWEVER! If you also didn't love ACOTAR, fear not, because ACOMAF is a billion times better. Seriously. ACOMAF is well aware of the Tamlin problem and it's made clear in the first chapter how unhealthy Feyre's relationship with Tamlin has become. Feyre has given up control of her life, because that's easier than fighting for herself, and her struggles to reclaim herself are both painful and relatable. Her journey toward acceptance - of who she is, of what she's done, of where she belongs - is breathtakingly written and Sarah has outdone herself. This book is allll Feyre, and is the better for it. You may be thinking there will be a love triangle, and a love interest (who is not Tamlin) does appear, but I definitely wouldn't call the situation a love triangle. I don't think anyone would (or should), and the reasons for that become apparent pretty quickly. 
 In short, I want to live in this book. I'm about to reread it for the first of what I'm sure will be many times. 
 I did have one issue with the book, which is (view spoiler)[ how Rhys imprinted on Feyre and didn't tell her. That was really disappointing and I wish SJM hadn't made imprinting a thing. It made their relationship feel sort of cheapened, like Feyre just spent the whole book getting her agency back and then this made it seem like all that agency was taken away again. (hide spoiler)]