There is lot of tosh being talked about above e.g RAF SAR costs hundreds of millions etc. The RAF costs are in tens of millions, under the current MCA contract Bristows only provides 4 x S-61s at a cost of £17M (check out the MCA's business plan). RAF SAR provides two aircraft and crews at each fllght location. (Granted the second cab is only serviceable around 50% of the time.) The OCU also provides additional surge capacity. The second aircraft/crew and the OCU aircraft/crews have been used repeatedly over the years for large scale incidents.
Also, the MCA cabs are primarily for maritime use. The aircraft don't have an NVG overland capabilty (and only carry out night coastal work). Over 50% of the RAF/RN SAR effort is overland, so this capability is important. And as an aside, it wouldn't be DTI or even DfT who'd pay for overland SAR as this is the repsonsibility of the Home/Scottish/Welsh/Northern Ireland Offices (enacted through the local police forces).
As for pipe and slippers...that betrays the age of the correspondent rather than the reallity that has existed for over 15 years.
I love a misininformed and prejudiced debate!