Had a TNN for a couple years now. I am on 'list' for the Cimarron 'longer barrel TTN' when they come in,,,,,they are indeed tough guns and performe very well.
I'd love having one in the 3 1/2 mag, 12ga,,,,but I doubt there would be much of a market to others for it.. and I'm sure they won't make just one....I believe it would hold up nicely to the super mag round though.
a 10ga'er would be pretty neat, just that the 3 1/2 , 12's are readily available at ya local Walmarts.
MD