Prometheus Hopup w/ strike chamber
 

Has anyone tried one of these? Having problems finding a review.

Best hop-up for the M4/M16 line in my opinion. They used to charge the same just for the strike chamber (the orange parts it comes with, top hop-up arm and gear), and it was still worth it, but now you get the hop-up as well.

The strike chamber makes it easier to fine-tune the hop-up, and makes it so it doesn't slip backwards as well.

You'll need the lower 2 gears from your existing hop-up to make it work.

Do you find any difference between who makes the gears? Inoticed G&P gears tend to want to undo themselves more frequently than TM ones.

Nah, brand of the gears doesn't matter.

best system out there - doesn't matter what brand gears you have, as long as you have the Prometheus hop up chamber, it will hold the gears in place.

(pretty simple fix, actually... it's just a rubber o-ring providing friction so that the gears don't undo themself as easily...

So in other words, as long as you use an o-ring...

... then it will hold the gears in place.