Gets rid of that rush to get your tank off so you don't ruin an O-ring or loose all your CO2. Easy to turn on/off. I love it, its a great improvement over a pin valve!
Weaknesses:
A little pricy. Guy charged me 15 bucks to install it! If you turn it on when its off of your gun, you'll get a huge spray of CO2 in your face. (I always learn the hard way :)) Not the valves fault but when you turn the valve off when its on your gun, there is stil about 20 shots worth of CO2 in the gun (I thought you just turn it off and there is no more CO2 left in the gun) so if you take it off with the CO2 still in the gun, it all rushes out just like before.
Conclusion:
Its worth what it costs, although I think I got ripped off on the installation. I think it is a very handy item to have if using CO2. I would definately recomend this to any player. After firing off the extra CO2 in the gun after turing valve off, it unscrews very easily without any worry. Overall, I love this product.