Just checked pricing for KUL-LHR mid-March on MH4, having done the same prior to the overnight Flicking of the Switch:

• Flexible Business Class – MYR12,168
• Business Suites – MYR14,747
• Flexible First Class (as available pre-Dec12) – MYR21,303

Interestingly, the second of Malaysia Airlines' two daily Airbus A350 Kuala Lumpur-London flights – MH2 – showed two of the four Business Suites selling markedly less than business class, at MYR16,247 versus MYR19,090.