They are OK. But only OK.
You get the basic moves but nothing really advanced and limited routines only fairly well done. Sal isn't any better at it that I am and I'm NOT boasting!
For the 3 card monte I'd recommend Daryl Does the Full Monte or Notes on the 3 Card Monte by
www.schoolforscoundrels.com. The notes are ludcrously comprehensive. The Daryl vid/dvd teaches you nearly every move known and 3 really excellent routines. He does the moves perfectly and is a good teacher. It's a gem. One of the best DVD's I've ever bought.
For the shell game I'd recommend you buy the booklets: Super Shells by Gary Ouellet for a routine. It's a real magical fooler with all the instructions on all the moves and even how to make up shells. The finish has the pea dissapearing from under a shell which is under two boals and appearing under another shell which is under a glass.
To get the real street moves (Sal doesn't really teach the street moves but merely performs on a street - not the same thing) and psychology then get 3 Shell Game by Ralph Read - not only does it cover all the real work but has a new pea moves that allow you to show your hands empty when they are not - again Sal uses a 2nd rate alternative IMO.
If you absolutely must have a video source for the shells then Bob Sheets' Absolutely Nuts is rated.
Check out
www.threeshellgame.com and
www.schoolforscoundrels.com