the synthetic sawn 'flint like thingies' are an abomination and should be banned from use by the civilized world ...
French Amber flints look pretty cool, but in my experience they work no better (though certainly no worse) than black English flints... all you get is that they look cool ... if you want to spend extra money to look cool, well that's your right: they're your over taxed, God entrusted dollars to spend as you see fit; don't let anyone make you spend them in a manner inconsistent with your desires.
(we call it confiscation where I come from, but some call it 'fair tax policy' - that's the political rant for today)
I have heard of but not seen flints which are cut (I would guess with a diamond wheel) ... don't see why these wouldn't work ...
so, in summation:
English flints? sure - the standard
French Amber ... pay for pretty - it's your call
"cut" flints ... why not? makes them fit in the cock
'synthetic' flint- like gadgets?
:slap:
i'd sooner put a dried cow patty in my lock ... probably get more spark, too
make good smoke!