I would suggest a completely different rig but its not cheap. You could at least add a secondary reg and some new gauges.
To me the rig you have now could use some QD fittings and a new gauge. You really want to know how much PSI you are putting into the gun since a difference of 20PSI could equal 100+FPS. You also could benefit from a secondary regulator to help smooth out your PSI and improve its consistency. CO2 is not the best choice but if you are trying to hide it then I guess it will have to do. If you can afford to use a Camelbak to store a HPA tank I would do that. In fact, that is exactly what I do.
For those that love this cold shot thing. The Mini reg used in it is a AR-10 which is sold at Poweraire (
http://www.poweraire.com/modular-regulator-ar10-p-2552.html ) for $13. I don't think it should be asked to overcome the PSI of unregulated CO2 but... Making a cold shot is pretty simple and the parts are out there. If you want something that is a little better you can always connect the cold shot , or a copy of it, to a palmer pursuits female stabilizer (airsoft 200PSI type) and run CO2 or HPA bottles.
I personally find the AR-10 lacking options in the gauge section since all you really want is big picture of the PSI between 50-150. And those tiny gauges barely distinguish between 10PSI. Not as small, the AR-20 uses bigger ports and allows for more options. Once you start using a primary and secondary reg you can adjust the 1st to 1-3PSI more than the 2nd. Once you have them VERY close your consistency is much better.
