I got a dinky electronics repair kit that included a wide range of those bits and god DAMN. It feels like they outperform phillips heads on phillips fasteners.
JIS is more common on Japanese machines, ie Japanese cars and motorcycles. When I was a bike mechanic you used JIS for Shimano derailleur adjustment screws. Even tho a Phillips "fit" it would destroy the screw.
I actually can't tell them apart from sight truth be told, but I'm also not wrenching anymore (not to mention the cycling industry largely moved on to hex and torx)
Probably. I find a JIS driver is, for the most part, slightly better for a lot of what I do.
The main thing I've found is you dont want too much of a point on the bit end. Too pointy and the driver will just wobble on the point and strip everything out.