I think I remember that the Strion and Stinger bulbs would fit in those lights. So, if the cells physically fit, that should work, but you'd have to make sure you're not to overdischarge the cell. A Pila 168 cell would eliminate this risk. Anyway, other than the possibilty to switch back to the original bulb and cr123's I see no advantage in buying a Nf-2 or Tl-2 just to make them what the strion already is. By the way, would two cr123's and a scorpion bulb work in the strion? Of course one would have to make sure not to put it in the charger with cr123's installed. But one could carry a scorpion bulb and two cr123 for emergencies when there's no possibility to recharge the strion.
Chrisse