I substituted a magnetic tailcap for the one with the light. Solved the drain problem, but now its a twisty. That's actually another benefit of the Tool AA - it can be a twisty or a tail switch.
The Olight i3t 2 will run on AAA alkalines, NimH rechargeables or a 10440 lithium. I have a Skilhunt something or other and it runs on AA alkalines, NimH rechargeables or a 14500 lithium. The Reylights I have also have that versatility. I like the idea of rechargeables, but also like being to able to pop in some alkalines in a pinch. I bought an inexpensive charger so I don't necessarily need a port in the light or battery.
BTW, the Streamlight 1l-1aa will run on a cr123, AA, or AAA. Pretty good little light.