We use CMM Technology to calibrate our onsite breathalysers every six months, CMM staff are always friendly and timely in their online responses and always friendly when on the phone.
CMM are also extremely prompt in testing the equipment and returning to us within 3-4 business days total turn around (which is amazing seeing as the units have to travel from one side of the country to the other outside of the next day delivery areas) leaving the organisation with only a small amount of time without this coverage.
Could not be happier with the current level of service supplied by CMM.