To do a proper comparison you would need like a dozen to a hundred of each make and they would need to be the same size....
But those graphs are close enough to be considered basically identical in my book.
This means the only difference between the two is an option..
The Iota with IQ-4 is, Im told (have not tested) equal to the Charge Wizard in the 9200 and other built in wizard PDI converters.
HOWEVER,,, it does not have an optional dongle.. IF you know how to use the dongle, this gives the advantage to the PDI. If you do not, then no difference.