Chemistry - N-fluorosuccinimide: any scope?
Maybe NFS doesn't work well? Bear in mind that bonds from a second-period element to fluorine are generally stronger and less labile than the corresponding bonds to heavier halogens. If that's true, getting fluorine off a nitrogen-fluorine bond requires more work than, say, getting bromine off a nitrogen-bromine bond.
In https://en.m.wikipedia.org/wiki/Electrophilic_fluorination#Mechanism_and_stereochemistry several common fluorinating reagents are given, these being the compounds mentioned by the OP. The listed compounds all withdraw electrons from the nitrogen-fluorine bond more strongly than the carbonyl groups would in NFS (they use sulfonyl groups or a cationic function), so it seems this attribute is necessary to get the fluorination to go.