There are several threads about these already. At least one member used these exclusively to build his power supplies (several 12V supplies in parallel). I have a copule of them that I assembed into small project boxes for use to power my LCD (12V) and USB stuff. They worked just fine but ultimately I didn't need them.
You can more information and datasheets direclty from the TI website. Limited free samples are also possible -- if you qualify.