Antec P150 needs the front 92mm fans?

Just wondering if I buy the P150 whether or not I should consider purchasing the additional fans for the 2 x 92mm fan slots at the front?

I would like a quiet system but hopefully 2 fans at the front running relatively quietly(ie low settings) will help keep the inside cooler through better airflow and reduce the speed at which the other fans, both internal and rear exhaust, will have to spin thereby giving my a quieter system overall?

I believe the top of the 2 fans is useful for helping keep your hard drive cool, I am going to be using a WD SE16 250GB drive there.
The 2nd fan mentioned that it may help airflow towards the graphics card, this would be particularly useful to me as I am hoping to get the x1800xt and I hear they can get exceptionally hot/noisy. I am going to be replacing the GPU fan with a zalman VF900-Cu as I hear this can really improve cooling as well as noise generation but again extra cooling in this area would be a huge plus.

Any opinions or experience of this kind of set up would be really appreciated, thanks