Since the Bosch is no longer an option
It is, it's just hard to get hold of.
Is the Nighthalk H6054 still the best beam available?
The best sealed beam, yes, is this one.
Also, is the H4 or LED that much better?
Good H4 lamps (Cibie would be the ones) with good H4 bulbs would be well worth considering. Good LEDs (Speaker or Truck-Lite), too. Cheap H4s or cheap LEDs would not be worth messing with.
I'm not a fan of PnP HIDs due to the glare to oncoming traffic. Unless their projectors
Even if they're projectors, "HID kits" are unsafe (and illegal).