-Only two adjustment screws
-Tough on the o-rings on the inside.
-Two Pieces. The knob that you turn is the same piece that depresses the pin in your tank, meaning that it will de-gas when you unscrew it, instead of the pressure holding the o-rings in place like with the Trinity.
As with all CCM products (imo), the pieces fit together beautifully. You can really tell that the tolerances on their products are tight.
I've used this ASA for a few years now, and it works great. It tends to chew up the little o-ring that goes on the shaft a little, but it has never leaked on me, and always seals.
It does what it needs to do, and does it better than some others I've seen out there.