I understand that one of the advantages, besides opening a Thai bank account and driving licence is being able to obtain Thai health insurance at a much reduced rate.

Does anyone have this health insurance and if so what companies in Thailand offer such a policy for foreign students.

Students at 'regular' schools usually have a group policy, with limited coverage that costs them a couple of hundred baht a year. In my experience, this was a required fee, and not an elective to purchase insurance on your own.