I just fitted a Power Plenum to my Gen 1 25 cal Impact. Works like a dream. Shooting the 34 grain JSB's, dropped the reg pressure from 145 bar to about 110. Still haven't finished tuning, but made a huge difference.
I'll probably install Dubber's Slug Power Kit to see if I can get a bit more efficiency, and drop the reg pressure to around 100 bar.
Ernest Rowe did a video on installation. My PP came in assembled, so didn't need most of the info in the video, but good to have anyway. https://www.youtube.com/watch?v=QDvHYGXnJgc
If you don't mind tearing your gun apart, you can install it, but if you want someone else to do it, I believe Utah Airguns will do it for a reasonable fee.
