When wearing hearing aids you can realistically expect that:
-Your hearing in quiet environments (one to one communication watching TV, etc) should be improved.
-Your hearing in moderate background noise should be improved.
-Your hearing in background noise is NOT going to be as good as your hearing in quiet.
-Your hearing in loud background noise should be NO WORSE than without the hearing aids.
-Soft speech should be audible, average speech should be comfortable; loud speech should be loud, but never uncomfortable.
-Your earmolds should be comfortable.
-Your own voice should be "acceptable" to you.
-There should be no feedback when the hearing aids are properly seated in your ears.
-You may hear sounds you have not heard for a while (like footsteps or the refrigerator humming). This is not abnormal.
-Be patient. It requires time to adjust to hearing aids. Your listening skills should improve gradually as you become accustomed to amplification.
Hearing aids WILL NOT restore your hearing capabilities to "normal" or to pre-existing levels. Hearing aids will help you experience a better hearing experience with your current state of hearing loss.
Source for this document: http://www.audiology.org