What's the word? Who likes which and why? l put my buddy's L4 on my car in place of my freshly rebuilt NH the other day and the engine liked it better. My Holley runs beautiful and idles right down to a "no throttle" setting... but gives a flat spot at 37 mph. l give it more juice and she gets past that spot and settles in a nice 43 mph. The L4 just moves right along without that glitch.
I can't give a comparison as I've never run the NH, I've had an L4 on my '27 since I've owned it and like it fine. It's easy to overhaul and runs great. The only problem I've found is there are some parts that are not available from vendors. I've picked up 2 or 3 decent, complete carbs off of eBay thru the years to use for parts.
I have L-4 on both cars and they run fine, the NH has a larger opening for more air and more go.
Rick