I don’t remember reviews for DAD, honestly. And I guess we’ve never really established in this thread what “underrated” even means. Some films like DAD made lots of money on release but are not well loved in hindsight. MR made crazy money and got some glowing reviews but is now the poster child for “bad” Bond (unfairly, but still). Other films under-performed financially by Bond standards but have their champions, like LTK. I have no idea how QoS did at the box office but I don’t know anyone outside of dedicated Bond fandom who cared for it.
So does “underrated” mean “unappreciated by the masses but beloved by fans in the know?” Does it mean “unloved by Bond purists but quite good if you’re not so unyielding in your mindset?” Does it mean “didn’t make a splash at the box office but deserved better?” I don’t know.
“Overrated” is a whole different subject, and maybe should be a separate thread, except by its nature it’s going to end up negative where this one is aimed at being positive.
Just in general, I’d say that the world at large only knows a handful of Bond films by name and any other entry could potentially end up on this list. I would submit that maybe “underrated” should mean “largely ignored compared to the two or three films that get all the love.” For instance, is “Goldfinger” really that much better than OHMSS, that every Joe on the street knows the former but would probably give you a blank stare if you mentioned the latter? Maybe we could rephrase the question to say, “If you could turn someone on to the merits of any less-celebrated Bond film, which film would that be?”