Yes use the extra bracket,it will work,use one or use both fans for a push\pull config.
Ah that is good to hear!
I am in the UK, so don't have easy access to all the same fans that appear in benchmarking tests. However, I have been doing a bit of research, and have found the following 4 fans. I know that the given dimensions for the Hyper 212 Evo fan are "120x120x25 mm (4.7x4.7x1 inch)" , yet don't know what to think about the fan speed specifications "600 - 1600 RPM (PWM) ± 10%". These were taken from the official website