Hasselblad say : "CFi and CFE lenses feature a list of improvements on the basic CF lenses that together produce an increase in image quality, reliability and convenience in operation. They include:"
* new internal design and new anti-reflection materials reducing stray light and enhancing the image contrast
* improved design and a new main spring extending life expectancy and increasing precision
* PC-socket with positive lock
* redesigned focusing mechanism
* reinforced rear bayonet
* front bayonet in durable non-metallic material
* new external design for comfort and style
The E adds the databus with AFAIK no other difference to the CFi
The font on the markings is different, presumably covered by the last point above, and is easier to read.
In use the flare resistance was noted as being most noticeable. I have some i versions but not the Cf equivalent so cannot comment.
The CFi should be priced between the CF and CFE.