I see nobody has mentioned Viscount/Lambert. This is as it should be. lol
I have one Bob Jackson, two Vikings, a Robin Hood, a Dunelt, and a bunch of Raleighs.
The ones with the best build quality are the 2000 Bob Jackson, 1977 Team Professional and 1970 Professional. The two Vikings and the 1949 Clubman have a very good build quality as well, though not quite as refined as the first three. The rest are all over the map, but are none-the-less enjoyable riders.
So many of the British builders had "lines" with various types of bicycles at a range of price points, so it is really difficult to come up with a "top ##" list without being very much more explicit about what you're including.
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