Hi,
cutting aluminum is always loud - especially on a large gantry that acts like a nice sound-box.
The spindles are available for 110V from some buyers at request.
However: neither wood routers nor those chinese spindles are well suited for aluminum. Both are fine with tool diameters up to about 5mm. But for larger diameter they just lack the necessary torque at lower rpm.
So take at least the 2.2kW spindle - you'll never need 2.2kW but at lower rpm it at least has considerably more torque than the 800W version.
My CAM Software and CNC Controller: www.estlcam.com