where I live you would need one on your head and one in each hand - with all the horrible roadworks, new traffic lights, traffic cones/rails. Holes in the ground etcetera etcetera
My OH carries a very heavy long torch, recommended by a police officer after a disturbing encounter one night. He said she was within her rights to carry it and should she use it for self defence, all well and good.
Tony has mentioned Cree LEDs. These type of LEDS are most certainly NOT much of a muchness !
They are a lot brighter than ordinary LEDS, so any torch using them doesn't have to be huge to be effective.
We have a very good ironmongers near me here in South Wales, where they stock an amazing variety of torches....garages also have them for sale.
This is similar to one that I keep in the door pocket of my car, and I can heartedly recommend it. It has 8000 lumens ! It also seems to last for ages on a set of batteries :::::