Not officially recorded (obviously), but there were several Bulleid Pacifics 'caught in the act' so to speak, by recorders in the last years of the LSW main line steam.
34042 (102mph), 35005 (105), 34013 on two occasions (100 each time), 35023 (101), 35007 (102), 35028 (103), 35003 on four occasions (100, 101, 106, 105), 34102 (100), 35008 (102)
There were many occasion when locos reached the mid- to upper-90s but were prevented from going further due to scheduling or signalling reasons.
Usual caveats as to accuracy apply...