I like NID's. I thought I was the only one, a lot of people think they are ugly.
I also don't like 21's (I find them boxy like K80's and ugly, they also have issues with ribs and the thinggie the forend attaches to under the barrels failing.
Its America, buy what you like and let the other guy do what he wants.
As an investment the 21 might be a better choice