UKBA's (published in the name of Rob Whiteman) newest monthly newsletter for stakeholders discussed the Settlement Checking Service. This was a rough analogy to the already established Nationality Checking Service where they look at all your stuff and see if you qualify and then return your critical documents.
The SCS ran in a pilot project up to November last year, and now they want to go live with it. The roll-out will take place over 2012, and there's several local authorities ready to go live right now.
The 'big picture' plan is to merge the NCS and SCS into a single body called the Immigration Checking Service.
Whiteman goes on to say that the list of local authorities authorized to provide this service are now listed on the UKBA site, but I can't find it.
I think using the SCS is a good idea because ILR applications can sometimes take a long time and you might need your critical docs while the application is being processed. It also helps to remove ambiguity on the suitability of your evidence because somebody is giving it a cursory once over. It's good value for money.