and then there is tyres...
When SV operated TriStars (their first widebody aircraft), they used exclusively flap 18 for take off, most other operators using 10 (the TW guys didn't like it, but did as they were told).
The reason was quite simple...lower Vspeeds resulted in lower tyre speeds, and to the best of my knowledge, never had a tread separation on the L10, at least up to 1990.