You are talking about getting an Angel or a Cocker. Well, why not the best of both worlds and get an Excalibur? It is closed-bolt like a cocker and fast like an Angel. It is low pressure (180psi), it has the best reg (AKA Sidewinder), it is very reliable, it is very efficient on air, you can also use co2 should you want to, it has a great lifetime warranty through AKA (a very dependable company), and you can get it for the price of an Angel or less.
In other words, I higly recommend the Excalibur.
Or, if you want to save money, ou could get an AKA Viking. It is open-bolt. It is better than the Angel in many ways. It goes use lower pressure, it has a better reg (AKA Sidewinder), it is more efficient on air, you can use co2, it has a lifetime warranty, it is just as fast as an Angel, it is as reliable or more reliable than the Angel, and the retail price is only $775.
You can't beat that!