The torque effect is the first thing one notices. Right brake must be applied with moderation or else you will perform a wingover. Left brake must also be applied with moderation to prevent a spin. Some simple devices can reduce or eliminate the torque effects such as a diagonal adjustable cross-braced strap, a longer carabiner to the right riser or asymmetrical speed trims. Noise is obviously a problem not only for your neighbour 1 mile away but your own ear drums a foot away.
Ear defenders are essential.
The high revving propeller carries an obvious amount of danger not only to you but also to the public. Extra line from the brake handle must be tied or cut to avoid hitting the propeller when forward inflating. Finally, a paramotor allows you to fly through the wake of your own wing and propeller with possible unpleasant bumps and an horrible exhaust smell.