velocityg4
Glorious
Diddo on those fans. They have good pressure and performance. They use a cheap sleeve bearing which don't last very long. Especially if the fans are under heavy load as you are expecting.
If you are dead set on additional case fans. You won't do much better than Noctua F12 iPPC-3000 (IndustrialPPC). Two of those will give you all the air you'd need. Other high end ones are the Corsair ML120 Pro and Noctua F12 iPPC-2000. In the Mid Range you can look at Corsair SP120 and Noctua NF-F12.
If you are dead set on additional case fans. You won't do much better than Noctua F12 iPPC-3000 (IndustrialPPC). Two of those will give you all the air you'd need. Other high end ones are the Corsair ML120 Pro and Noctua F12 iPPC-2000. In the Mid Range you can look at Corsair SP120 and Noctua NF-F12.