There's no comparison really. The Nano is 5x the rod the Ethos is. I have 2 Ethos that I got as a gift, I'm not a big fan. They're severely underpowered. I use the 7' HEAVY for fishing weightless worms ffs. And the sensitivity is average at best. They make good moving bait rods but beyond that I don't like them. The Nano is way better quality rod, much more sensitive, lighter, stronger too.
With that said, the Nanos cost $90. . .you could spend $10 or $20 more and get a 13 Fishing Omen Black and have a rod that's worlds better than a Nano.