All of the countries I've been to have been hit and miss, two good examples of this are Vietnam and Thailand. I wasn't a huge fan of either Bangkok or Hanoi, after hearing about how 'outstanding' these cities were, I just couldn't get into them. Hanoi was dreadful, absolutely nothing to do, and the place was a serious mess, but then there was Halong Bay which was one of the most beautiful and natural places I've ever visited, and I'd happily spend hours walking around admiring the scenery.
Bangkok was mainly down to my condition at the time, I was really ill and it was back when the Swine Flu pandemic was at it's highest, I was one of the unfortunate many to get this. So I found travelling around the city a dangerous move, but I still did it, but despite passing out from dehydration twice in 3 days (the humidity was insane, peaking around 97-98%), it was an interesting city, which was shamefully destroyed by the slum-like areas and down-right mess. I couldn't enjoy the city, but I may have to visit again to feel the real vibe. On the other hand, there was a tiny island off the coast of Thailand called 'Phi Phi', this was the most stunning place I have ever visited. Anyone who has watched the film 'The Beach' would know that. Also had a soft spot for Phuket too, that place was great fun (despite it being the Thai equivalent of Benidorm..).
