It's not a case of changing the fan, in fact that's not possible.
The V2100 is available in 3 flavours:
V2100 - no fan at top of case, rear fan acts as an exhaust
V2100 Plus - crossflow exhaust blower at top of case acting as an exhaust through the back panel, rear fan is an intake.
V2100 PlusII - crossflow fan replaced by axial flow (normal) fan exhausting through the side panel as per Veee's photo. Rear fan still an intake.
I *think* the Plus has been replaced by the PlusII so chances are you would get one with the quieter fan anyway.