This summer has unexpectedly turned into a showdown between two heavyweight authors: Harper Lee and E.L. James. Lee’s long-awaited (and, before last year, heretofore unknown) sophomore novel, Go Set a Watchman, seemed primed to be the big of book of summer. Then, two weeks ago, Random House announced another title was coming in the Fifty Shades of Grey saga—Grey: Fifty Shades of Grey as Told by Christian. Now both books will be vying for the title of the season’s biggest seller. Grey is out first, June 18, with Watchman due to be released July 14. Here’s a look at how these two novels stack up.

Go Set a Watchman

...is tied to a famous bestseller

Its predecessor, To Kill a Mockingbird, first published in 1960, is considered one of the top-selling books of all time. The novel has sold more than 40 million copies and continues to sell roughly one million copies a year across all formats.

...has its fans

Publisher HarperCollins has claimed the novel is its highest-selling preorder title of all time.

...has its detractors

Book critic David Ulin, writing in the L.A. Times, admitted to being curious about the novel but said it remains a work “that was rejected and then ignored for 60 years.”

...is written by authors who’ve had their detractors

A 1960 review by Phoebe Adams in the Atlantic called To Kill a Mockingbird “sugar-water served with humor.”

...has its publisher’s support

Go Set a Watchman is getting an announced first printing of two million copies.

...is tied to an influential prior novel

Some cite To Kill a Mockingbird as encouraging more people to become lawyers in the early 1960s.

...is written by an award-winning author

Harper Lee won the Pulitzer Prize for fiction for To Kill a Mockingbird.

Grey: Fifty Shades of Grey as Told by Christian

...is tied to a famous bestseller

The Fifty Shades of Grey trilogy is considered the fastest-selling adult series of all time. Publisher Penguin Random House has said the series’s global sales exceed 125 million copies since the release of the first book in 2012.

...has its fans

Less than 24 hours after being announced on June 1, Grey shot to #1 at both Barnes & Noble and Amazon and also hit #1 in the Apple iBooks store.

...has its detractors

Jezebel wrote, “It’s just absolutely wonderful news for literature lovers all around, setting a precedent that... will bring us Lean In from the perspective of a middle-class woman, The Fault in Our Stars from the POV of ‘our stars,’ and Unbroken in the voice of Seabiscuit.”

...is written by authors who’ve had their detractors

A 2012 review in the Telegraph, by Laura Bennett, called Fifty Shades of Grey worth picking up “if you come prepared to wade through pages of treacly cliché.”

...has its publisher’s support

The new book is getting an announced first printing of 1.25 million copies.

...is tied to an influential prior novel

Some credit Fifty Shades of Grey, which was self-published, as overturning notions about the publishing industry.

...is written by an award-winning author

James was named PW’s Publishing Person of the Year in 2012; she was also included on Time’s 100 Most Influential People list that year.