I am also thinking about going the extra and purchasing a compressor. Really not sure to get, but I didn't realize the expense.
The Air Venturi is going to cost around 1300 dollars. OUCH!!!
The Nomad would be around 700 dollars.
The two things I don't like about the Venturi is of course, the cost, and also it weighs around 75 pounds. But you can refill your 75 CU. FT. tank, and just about anything. Now I doubt if I am going to be moving this rig much seeing I have a big tank, and can always just fill it when I am going out to shoot.
The Nomad I don't believe you should be filling the large tanks with. If I was to purchase another cylinder for the FX, I would have at least 150 shots before I would be looking to refill. I have never shot that much in a month, let alone a week.
Just not really sure which was to go at this time.