From Smith's web site, both of these are grandfathered as of 1.1.2014 as far as i know. Only. 400B was sold over 6,000 units. ..
The IMS detectors in the IONSCAN 500DT are the same as in the IONSCAN 400B, of which over 6000 are in use by aviation security, government and law enforcement agencies, the military and by private security companies. Further advancements include full PC functionality, increased memory and networking capabilities. An advanced sampling wand eliminates the need for the operator to handle the sample swab after every sample. This increases the quality of the sample.