Just tried U200 and TMS4, was denied both, stating "I cannot find them in our system" and "...after speaking with my supervisor, we don't offer those anymore."
I don't think it is tricking, but rather an example of poor training - which isn't any better. Add to that the complexity of the thousands of FAN accounts out there, each with its own set of eligible codes, I can understand how confusion can set in.
As I understand it, each FAN account has access to the same SOC codes. The differences in FAN accounts have to do with the discounts you recieve, access to unlimited upgrades, etc. I THINK the SOC codes are standardized.