As someone mentioned, the NGX controllers can be modded to work with NG. I've seen a number of pre-modded ones on eBay, although I don't know what the quality difference may be between NGX and original NG controllers.
The answer to your question... it's garbage. The quality is garbage. You pretty much have to gut the entire stick out of the buttons and the micro switches in the joystick to even make it serviceable so you're probably looking at another $25 in parts. It's much more cost effective to just find an old PS3 or Xbox 360 arcade stick with quality parts in it already and rewire it with a Neo plug. I have modded and rewired a few NGX sticks out of curiosity and just a hobby project. I can tell you that you can probably find an authentic AES stick for the same price you would be putting into parts you need to replace in the NGX stick to make it work.
$40-$45 for the NGX stick
Around $15 for replacement buttons and switches
$10 for the Neo DB15 cable.
And that is not including shipping for these materials, and the cost if you do not already have the solder equipment on hand.