Wade Laube is a photo editor, a photographer and an opinionated ranter (the two last descriptions make him a "my-kind-of-guy"), and he's penned an interesting post on his blog titled Buyer Beware of the Dodgy Workshop.
He says this:
"The travel industry has offered photography-themed holidays for years. Hobbyists spend their annual leave somewhere picturesque, get expert tuition and access to expensive gear they wouldn’t normally, while the organisers make some money and everyone’s happy. But what aboveboard entrepreneurs started, parasites are mimicking."
And I couldn't agree more. Caveat Emptor is the rule here. I would also add that great photographers are not necessarily great travel photography workshop teachers and/or leaders. Some are and others are not.
Once again, here's Wade's wisdom:
"Ultimately what you need to ask yourself is whether you are purchasing a valuable educational experience. Are you just paying for the brand-value of a big name photographer and getting little more?"