I heard of a UAL 757 Jumping straight out of LAX and maintaining 6000ft/min climb profile at one point
..check out
www.airliners.net forums for more details,got a photo of instrument display VSI,350 kts,got to cruising altitude quickly needless to say!!!
In the UK..i`m not sure how accurate it is,I was a passenger on a Virgin 747-400,G-VROY,and after t/o they put on the skymap.
On there it displays altitude,airspeed and outside temperature,aswell as a cool mini-map of where your going!maybe scroggs could tell how accurate it is,but after t/o,bound for KMCO,at 4000ft we were at 330 kts according to the sky map,and weren`t on a SID as far as I could tell,think the only SID from EGKK from 26L west is SAM(2M)???
So yeah..the 250 rule can be broken it seems...
Stephen.