I got lucky and bought a used one off of fb for $65 shipped. I confirmed it was authentic, the seller had a receipt from pumaspeed, and when I received it I watched the youtube video describing the differences and this matched all the authentic features. On top of that the seller sent the top of his stock DV so I didn't even have to try to take mine apart! This was a huge bonus, since I really want to be able to return my car completely to stock if necessary.
The install was a bit of a pain, it took me about two hours from start to finish, if I did it again I could probably get it done in a little over an hour. I installed it from underneath with the car up on jacks, I wish I would have reviewed the thread below in more detail prior to starting my install, it probably would have helped a lot. I probably would do it from the wheel side from now on, but being able to see stuff from underneath would help too, so I would probably jack it up and take the wheel off. Also, the assembly fell apart on me multiple times so eventually I got some electrical tape and taped it together so I could get the assembly mostly installed, and then I pulled off the tape. My charge pipe was in the way, but I worked around it. It would have been nice to get it out of the way completely, but now with a full hard pipe it would have taken more time to remove it than it was worth. I wiped on some motor oil that I had with a paper towel for lube.
I took it for a test drive afterwards with some decent pulls, I will say it felt a little smoother but with the Dizzy tune it's pretty smooth already, and the 1-2 shift was helped a lot by the AWR RMM. The blowoff noise is definitely quieter than the stock valve, I kind of miss it now. Oh well, knowing that I can hold boost better and have quicker response is probably worth it.
https://www.fiestastforum.com/forum/threads/15304-HOW-TO-Install-GFB-DV-Diverter-Valve