Settlement checking service is only available for Set(M) applicants.
I think there are plenty of OISC (Office of the Immigration Services Commissioner) accredited immigration consultants who would charge a fee and check your application for you - just for your added peace of mind.
This link might be of help:
http://oisc.homeoffice.gov.uk/how_to_fi ... n_adviser/
I think if your too concerned and there is too much of stake you might probably just be better off hiring one of them to do the application on your behalf. I think they charge anything between £600-£1000 or thereabouts I guess.
Good luck with your application.