For parts changers that want to see how a balanced piston is done, or a G260-style second stage with a micro-adjust, there are four more videos out on the DGX YouTube channel covering their XTRA regs.
Lots of subtle repair tips buried there, but beware of DIY from a video alone! I have really mixed feelings about this stuff being out there.
There are a couple more videos in the works on their excellent value version of the integrated Inflator/Octo a la Air2 or SS1. The new BCI is a pretty slick integrated reg with a huge exhaust valve that's tunable down to 1" cracking effort! Not that that's a spec value, lol! Manual evidently still being written, but it's easy to service! It has a locking high-flow coupling similar to Oceanic or Poseidon, so reattachment in the water is a piece of cake.
Pretty impressive, especially for the price.