Riding Rollers or Trainer

There is definitely a learning curve to riding rollers. It is harder than riding outside. The usual recommendation is to start in a doorway so you don't fall over. Believe me you will fall over. Once you get the hang of it it really is super for balance and core.

My rollers are not loud nor is my trainer, but some can be.

Ambient noise levels depend largely the type of resistance device utilized.  A fan unit (the traditional 'turbo trainer' will provide the most realistic resistance curve as wheel speed increases, but is exceptionally loud.  Mag trainers generally provide static resistance levels (unless it is of the centrifugal variety), and are generally somewhat quieter than wind units, but still rather loud.  Fluid trainers provide decent resistance, and are typically the quietest of the three.   Resistance units are most commonly used on trainers, but sometimes on rollers as well.  Rollers typically depend upon the rolling resistance of the wheels/unit, and the ambient noise is limited to your drivetrain/rotating wheels.

For apartment dwellers, it's worth noting that most of the noise generated will be in the form of vibrations going through the floor.  Even relatively quiet rollers or fluid trainers can make the floor resonate, driving downstairs residents without an affinity for cycling crazy (back in college, I had a good friend who lived in the dorm room above me - while I rather enjoyed the rhythmic sound of his daily spins on the rollers, my roommate would escape to the library whenever my buddy hopped on the bike).