Although the prices appear to be very high (remember that there is no real substitute for an attendance course ), you sem to have narrowed it down pretty well. Do check out what other posters say about them on this site - use the search box to find out more, then make your final choice. Before you sign up for LTTC, send them a polite email asking if they have surmounted their problems with administrative delays and poor communications, telling them that you will probably take their course if they have, and can guarantee prompt attention to the delivery of the certificate. The course itself is actually OK - I have copy of it.
Intesol enjoys a good reputation and is accredited for the operation it conducts in the UK.