I bought once a box of this film, 4x5" that is. After a short while I realized that it made not much sense in terms of grainlessness as 20x24" prints are also pretty much grainless with usual 100 asa film.
Ability to capture detail is astonishing (if you follow the rules of engagement as described on the gigabit website).
One of the few test-exposures I made:
Detail: 25x enlargement (print would have been 100"x125")
taking lens was a SK APO Symmar 150mm (at f8 or f11)
print lens was a SK Componon S 80mm (central area enlarged to get to 25x)