i havent look at cams too close yet, but one thing i like (logically) is that a camshaft is 1 piece.
which means as long as its shaped 100% perfectly then there should be not much to worry about besides the looming concern of inferior metal blowing up.
engine internals are one place i would be devastated if something went wrong. so for that reason, i would probably get hks cams for peace of mind.
HKS is a good brand; we all know they R&D their products before they throw them out on the market.
like i said, i havent done very much research into cams outside of the differences between the various lifts and gathering info on powerbands and max rpm capabilities.
ive never read about an hks cam failure, but i vaguely recall 1 article about a brian crower failure (might not have even been camshaft though).
BC is not Crower, and Crower makes a point to not be associated in any way with BC, so that leaves room for thought in regards to quality.
do some reading into what material they use and how the BC cams are crafted; maybe that can reveal some potential reasons why there is such a cost difference.
you usually get what you pay for though.