Our disclosure for substitute checks says the check will have this written on the front: "This is a legal copy of your check. You can use it the same way you would use the original check."--but when I asked for copies of substitute checks for my Reg CC review, they do not have that on the front of the check. Could this be a problem?

Maybe. And maybe it's a question of terminology. Some people, even some bankers, confuse "substitute checks" with simple copies of checks. One will have the verbiage you describe and will enjoy the legal status of an original check; the other won't. What you are being given may not be substitute checks at all.