more than you ever want to know:
The "inspector" quoted from amazon is full of crap.
however, what you get out of a legal sealed beam halogen setup is about 700lm on the low beams and 1500lm on the high beams (55W low/65W high). You can improve the voltage at the light, but at ~12.8V, you get the maximum designed capability. Since the US primarily goes off of wattage, you have to use a wattage vs bulb technology chart to figure out the lumens. HIDs go as much as 3000lm but it needs to be applied through a proper projection lens.
Always amazed at the nervous nellies on this site. While you might get caught if you took your coach for inspection in a state that requires a yearly sticker, your chance of being caught with a non-DOT compliant headlight on the road is essentially zero. The CHP has bigger fish to fry. just don't put a full width 100 led array on the front and run down the highway like you're in the middle of the Baja 1000 at 2 AM.
The headlight experts LED conversion kit referenced above is a E-code assembly with a H4 compatible LED bulb in it. It looks like they took pains to put the LED in strip form about where the H4 tungsten elements are located, which means the light might actually go where it's supposed to.
I believe the 9600lm claim on the Amazon bulbs is a TOTAL of all four on high....not for each.
A set of E-code headlamps can be fitted with higher output bulbs without blinding oncoming traffic due to the beam cutoff, and you'll see more down the right shoulder as well. I have 7-inch rectangular e-codes with 100W low/130W high, so basically twice the output of DOT compliant sealed beams. There weren't LEDs available when I got these several years back, and they are much cheaper, but the power draw is considerable and the relay kit is absolutely necessary with a high-current draw halogen setup.