If you get an e-mail about making millions with these and you hear the names Greg Montoya or John Bender, don't be suckered in. They will take you for a fool. This is particularly important for parents whose children want to take classes. The biggest rip-off of all, that is rarely mentioned to new students, is promotion test fees. There is an extra charge for the test.
Some schools are reasonable, some rip-off artists.
Some schools will also require you to participate in tournaments in order to advance. There are good schools out there, but do your research. I am complain in g about two large corporations that do not honestly care about there customers. No 1 in the USA and world wide. Probably the finest cars ever built.