I got some excellent but fairly expensive ultra-bright blue LEDs by Agilent from Digikey or Newarkinone. Agilent is a spinoff of Hewlett-Packard and are American-made. You get to select the beamwidth, brightness range and tint range. The ones I have are all exactly the same, like clones.
Cheap Chinese LEDs aren't reliable, have different brightnesses and tints. Usually they focus them into a very narrow beam to be bright. I bought cheap Chinese LEDs to try and some didn't work and others were completely different colors.
Agilent says their LEDs are used in traffic lights. Even the blue ones!!!