Standto, that tragic incident just goes to prove that people can be stupid enough to get themselves into situations that they can't be rescued from - in this case it wasn't the lack of equipment or capability that lost the chap and his unfortunate son their lives, it was his decision to walk out there without considering weather/tides etc.
As for the pipe dream of multi-capable SAR assets liberally sited around the coast, who is going to pay for it? fundraising a la air ambulance? police authorities? the coastguard? At the moment the DTLR is very happy to let the MOD fund most of UK SAR from the defence budget as it a. fulfils their commitment to the Chicago Convention for SAR in our area of responsibility and b. doesn't require Gordon Brown to stump up the cash because it is already allocated out of a dwindling defence budget.
However watch this space - the military is constantly being pressured to cut costs and so far SAR has not been shown to be deployable (something which is very desireable in modern military thinking), it is an easy target for the bean counters and could so simply be sloped off the the DTLR to sort out.
Out of interest the RAF Sea King fleet is being upgraded with a FLIR turret over the next couple of years which should further enhance our capability. (that's each aircraft with a FLIR not one turret for the whole SAR force!!)