I'm sure SparKlites are generally well made but not as reliable as a fire steel or a piece of flint or even bamboo.
Kindly break your arm/wrist and then please demonstrate starting a fire with your fire steel. Please post video for us all to watch the fun...
The point being that "reliable" can mean different things, depending upon the circumstances. A piece of survival gear that does not lend itself to one-handed use may not be "reliable" at all if you only have one hand to use.