Most of you felt it was a valuable resource for your library, but the amount of usage was varied. Thanks so much for all your helpful replies. I have had Dialog for four years and use it as a vehicle to teach Boolean search strategy to the students. The company has been very helpful in that they will provide free training passwords and user numbers so that students can practice searching without it costing us anything. I don't know how Dialog's recent changes will affect that.
Students also use it for research when they have exhausted all other possibilities.
I have found it well worth the money and the company excellent to work with. As we understand there is no monthly charge. There is a charge for the time spent for online searching. I do not have the information with me presently, but I reached them through an 800 number. Another media specialist in our system loves Dialog for her elementary school.