I use a surefire, same thing basically as your redline flashlight you posted. I can't see inside of a pair of OE eggs I have in my 'bator, one is completely opaque the other is just a bit see through, but nothing clear. It can penetrate the marans eggs (not as dark as some of the really chocolately dark eggs), but again, not clearly. All the other eggs are very clear, bouncing embryos, veins, etc.
Since the batteries cost an arm and a leg, I only look in short bursts anyway.