Surefire / Ultrafire or any ’——’fire are, politely said, lower end consumer lights. There was an exception Thorfire, but has been superceded by the name Sofirn.
You want simple UI, Thrunite’s are simple and excellent. The TC15 comes with a battery* and built-in charging. Low / med / high. Double click to stun. Long press for moonlight (as for finding the keyhole).

Jumping to a FW3A, well that is not simple UI (although you could set up as such), needs an 18650 battery and charger. But if you want to dazzle (impress) someone or dabble / explore the many features of Anduril…

*Lithium Ion batteries are the prefered as they have some 3 x energy capacity of Alkalines, 4 x Nickel Metal Hydrides. Disposable batteries (CRA 123) are a constant pain in the @$$! NiMH are ok if you are already set up with a charger. They won’t give the outputs of LiIons.

@Macka17; Wouldn’t suggest an Astrolux S43. Gave one to a muggle and rather buying an 18350 battery for the shorty version, opted for a cheap 6500º+ Hi/Lo/red headlight for fishing. Would of had the perfect cap light.