I'll say this as a person working as a model & act...

I'll say this as a person working as a model & actor in the industry, Images from what I can tell seems more bent on making money off their talent in a very unconventional way. They make their talent pay for photographers and acting coaches that work for them. I've heard $2,500 for acting classes at Images. For $2,500 you could pay for "4" or "5" different semester base acting courses at your local university, college, or community college. Yes, a head shot is good to have, but it's not a make or break within the st. louis market. Now-a-days most casting departments ask the talent to send current digitals, because they are the most truthful medium in representing the persons natural look. As far as head shots are concerned a legitimate agency may suggest photographers for you, but ultimately it is YOUR DECISION who you want to have do your head shots. Their isn't any special in getting a good headshot; just as long as it is a clear, precise representation of how you currently look, then that's all you need.
I remember going to one of Images open-calls years ago, and they told me that they liked my head shot, but that the background color was wrong and wanted me to redo it with their person. They didn't realize that I had a background in digital-editing, so I told them that I could change the color to what they preferred. They still persisted that I get new head shots, and that I do it with their person. It became evident to me that they get a portion of the money from their photographer.
The agency I'm currently with did not pressure me to take any classes, or go see a specific photographer for my updated shots. I enrolled in a semester based acting course called "Acting in front of the Camera" that only cost me $250, and gave me 12 weeks of acting and auditioning practice in front of the camera. They also provided head shots from a professional photographer, talent resume building, demo work, guest-speakers from seasoned actors, etc. I have three commercials airing right now, as well as a print ad.
I encourage anyone looking to get into the industry to do their due diligence when it comes to finding an agent. This is a up-and-down industry, so make sure you have REALISTIC EXPECTATIONS when coming into it. Don't think that the second you sign with an agency that you will be booked as the next Progressive Spokesperson. Make sure that the agent DOES NOT require you to pay for anything you deem unnecessary. The business, especially the commercial acting side is straight-forward. If you have the right look that a casting director is searching for, then they'll ask you to audition. Casting directors won't ask to know what acting classes you took, especially if they are just looking to book extras on a job.