I have to say I got a little disappointed with this book. But maybe I have myself to blame for that, because I was expecting to be more obviously moved.
But Ishiguro isn't John Green, he isn't obvious, he is smooth, he just shows how the characters interact with each other and their situation, because we know it is sad for itself. So no emotional breakdowns.
The author also takes his time in establishing the characters, the set, etc. so for a time I sensed that the story didn't evolved, but that changes in the second half.
The ending is just crushing.
So, yep, the plot is so strong, so strong that for me it totally overcomes the problems.