I would love to do a comparison of a Nagler and Ethos of the same FL. The Ethos line is now fairly affordable with the 17mm at about $770. When the 13mm first came out they were nearly $1k!
With the 17 Nag at about $430, the Ethos is still a substantial bit more but they are both expensive, so my logic was in for a penny!
And if I had got the Nag, I would have looked through the Ethos one of these days at a camp and gone and bought one anyways!! So this way I have saved $430!!
Malcolm