I've just re-acquired a copy of the Quarrie/Airfix/Napoleonic Rules
In terms of British fire factors, Quarrie rates Fusilier Regiments on a higher factor than Line Infantry and on a par with Grenadier Companies and Light Infantry. When it comes to Mellee he rates them better than Line, Grenadier or Light and he gives them a higher moerale rating second only to Guard
It's the only set of rules I've ever come across that rated British Fusileer Batallions as anything but equivalent of Line. Equally in any reading about the British army in Napoleonic times, I'm not conscious of anything particularly relating to Fusiliers.
Can it be justified? Have I missed something?