The Devil's Chord isn't perfect.  It is practically begging to have writes to Beatles music production simply could never reasonably afford.  It's story is pretty simple and straightforward, perhaps to a fault.  And I do have to admit the last song at the end wasn't exactly impressive.

Yet I've always been quite deferential to this episode.  I had fun from pretty much start to finish.  Maestro was the most fun with a villain I've had in Doctor Who since pretty much we've last seen Missy.  Jinkx Monsoon did a great job embracing a very camp villain that absolutely lives up to the energy of such villainy from the Classic Who era.  Sure, the episode is missing some of the Beatles actual music, but there are a lot of musical moments I really like.  The Doctor and Ruby bringing the city back to life with their song early on in the episode, Maestro confronting the two and menacing the TARDIS, and John and Paul finding the special chord - all these moments build up on each other and got me invested in the story. It's my favourite aspect of this season - each story feels like a big adventure, with all the weight and length of a movie more than a standard television episode.  And yes, while there are flaws to the Devil's Chord, I really enjoyed that journey.