Not all of us can afford a Fishman Aura, so I found a good alternative. The Nux Stageman Floor normally sells for $150, but Wal-Mart is selling them for $92. It takes about 3 weeks to get them. I think their drop shipping them from China. They didn't even charge me sales tax or shipping charges.
We'll look forward to your report, but it's really an apples-to-oranges comparison.
Though the Aura Jerry Douglas pedal does boost the signal a bit, it's not really a preamp.
A preamp will of course boost the signal, but not having something like the Aura images on board, I don't see where this Nux unit will do anything to tame the piezo "quack" from the Nashville pickup.
Editing this post: In reading the description in the link below I see it does have a switch for "piezo" so maybe that helps with the quack. I have played directly into a Roland acoustic amp in the past with a piezo switch and it helped, but nothing like using the Aura pedal.
I received my new NUX Stageman Floor and I am very happy with it. I've never played thru an Aura so I can't compare them, but for $92 this sounds awesome. I'm using my pedal steel guitar amp with a 15" speaker. I have both the amp and Stageman scooped and the mids backed of the amp. The Stageman has a very high output so I have the amp input attenauted to -10db. I'd recommend the Stageman if you can't spend the money for the Fishman.