I was thinking about buying a wurkkos fc11 as my first flashlight but it said they recommend untwisting it in a review to avoid making a connection so it doesn’t discharge while not in use. Do I need to worry about that with all flashlights? I was planning on keeping it in my backpack so I have it whenever.
Mechanical switch lights like the Convoy S2+ do not have any parasitic drain. But be aware that the batteries themselves have some self-discharge, Li-Ions are the worst at something like 5 percent in the first 24 hours and then loses 1–2 percent per month. Protected Li-Ions are even worse at 4-5% per month.
If you need to keep them stored for long periods, get an AA-compatible or dual-fuel flashlight and use Eneloop batteries for rechargeables, or Lithium primaries if you don’t need/want to recharge.