Just slightly off-topic; I was watching The Man Who Cycled the Americas - Mark Beaumont on BBC4 last night and was (slightly) shocked when he threw himself on the mercy of the Guatemalan ex national race team mechanic to replace his bottom bracket bearings, totally worn out after ~7500 miles. The mechanic was astonished because the expected life of the bearings was 1800 miles. WTAF? I knew outboard bearings don't have the life expectancy of square taper, but wow, just wow!
My Bob Jackson, frame bought second-hand in 1980, is now on its third bottom bracket after around 40,000 miles.