I guess Trooplewis has a good take on the difference here
I have Crohn's so I make frequent trips to the bathroom even all throughout the evening/morning.
I've experienced a Trustfire SA-2 dying on me in the middle of a really,really dark staircase.
I've had the Ultrafire C3 flicker itself to death as well, all these within 6 months of buying them
--Sure not a matter of life or death - but what if it was?
It made me open my eyes more to the mid-range lights
Will I still buy budget lights? YES - but I will be more careful.