I've been there, done that, got the T-shirt.
Lately, LED ones have improved to the point where some now beat krypton, xenon and halogen ones.
Keep an eye out - every several months, some of these LED lights keep on leapfrogging each other. I am usually fairly happy with Dorcy and Inova ones with high power LEDs. Also look for ones claiming at least 80 lumens, even though I consider the lumen figures to be often from the marketing department.
A KPR3 higher power krypton bulb (usable in a in a 3-D-cell Mag), at "full 4.5 volts" (usually not achieved), produces about 95 lumens - before optics losses. It produces 44 lumens (before optics losses) at "nominal voltage", assuming typical alkaline batteries "of average of condition other than of batteries needing to be replaced", along with typical minor voltage drops in conductors in the flashlight.
One thing about LEDs - their efficiency does not vary directly and disproportionately with power input the way that of incandescents (including halogens, kryptons, xenons) does.
Most 3-cell LED flashlights, including many Dorcy and most cheapie ones, are good at "going into energy conservation mode" as the batteries weaken. They will keep on trucking at reduced but largely usable output for many times as much time as that at which an incandescent one gets as dim as an idling cigarette.