Pacemakers are absolutely safe. The technology has been around for almost 30 years now and continues to be improved. Millions are in use everyday. Safety also has to be assessed on a comparative level. Pacemakers allow millions of people with serious heart conditions to live productive capable lives. For many people, the 1% risk of device failure is much safer than death without it.
Yes, pacemakers and defibrillators are safe, because it is better to have a pacemaker than to have nothing at all. If the other option for a person with a bad heart is to die, it is fine for that person to want to try technology instead. Someone who has problems does not have other options, and they would rather have a pacemaker than die.
Yes, pacemakers are safe, and they save many lives that would have otherwise been lost without this technology. Pacemakers monitor the electrical rhythm of a patient's heart, and when it does not detect a heart beat, it will send an electrical pulse to restart the heart. Without these devices, many people would lose their lives.
I believe pacemakers and defibrillators are safe. I personally wouldn't want one because they sound quite scary to me, but they supposedly save the people they are placed in, if there is a problem. Pacemakers and defibrillators have been used for many years, technology I would identify as old and therefore tested and safe.