RP8008: Different countries different attitudes. ATC that is; which is what this is really all about. Boeing FMC's used to (may still do) default 240/100 to allow a 10kts overspeed. VNAV would control that. There is a perception, true or not, that some ATC's allow +/-10kts. High density STAR's use accurate speed for spacing & traffic flow, and they want absolute. Use what is necessary.