I added the FAE (Fresh Air Exhaust) to my 2014 Axis A24 at the end of last summer. Only used boat twice with it, and it was a big difference in engine noise, and exhaust smell for sure. Overall so far happy with it, however I will say as others have, the wedge is definitely in tight quarters with the FAE unit. Both dropping it down and picking it up are both easiest with a hand under the back of the boat and a hand in the hatch. If you can get up-pressure put on the wedge to release the weight of it, you can get to the pins fairly easy to drop the wedge. We've found it easiest to have someone push the wedge from in the water to both deploy it and retrieve it. Sort of a pain, but I think the benefits to the FAE out-weight the negative for sure. I will say the auto deploy wedge that came out this year would be awesome!
We pretty much leave the wedge down most of the day anyhow. So its not that big of a deal. One thing we haven't tried because we haven't been out at night is the rear LED's.. They are pretty much blocked and I would imagine not nearly as effective now that the FAE is installed.
I will say my main thing was the smell of the exhaust at surf speed. I have the 409 motor, and not sure if they all stink like this one, but it was pretty bad for folks at the rear of the boat. Kids and adults were complaining about it. It definitely has helped a ton with that issue. My stereo is awesome so wasn't as worried about getting better stereo sound. But that is surely a nice plus too.
Here's some pictures: