"We do have to give them the realistic option of being freed,..."
No we do not, Jim.
In February of this year the Court of Appeal ruled that the imposition of whole life sentences was allowed for the most serious of crimes. They did so when they increased a 40-year tariff to a whole-life tariff for murderer Ian McLoughlin, whose trial judge had said he was unable to pass such a sentence. At the same time they also dismissed an appeal by murderer Lee Newell that his whole-life order had been "manifestly excessive".
The European Court of Human Rights had ruled such terms breached human rights (and who would have expected anything less). In July, the European court said that while it accepted whole life orders could be justified, there should nevertheless be some way of having imprisonment reviewed after 25 years. Fortunately (for the time being at least) the government has ignored that ruling.
I remember the 1966 killings (in Shepherds Bush if I recall correctly) and if ever an individual deserved to be incarcerated for the rest of his days it is Harry Roberts.