I hope the newer wheelpilots are more robust. We had a 1990 vintage wheelpilot on our 35' sloop for several years and it repeatedly failed, always at the most convenient times. When it was working, it did not inspire confidence as the wind picked up.
If you aren't trying to fix and existing one and haven't committed to a wheel pilot purchase, we strongly recommend taking a hard look at a below deck pilot, which is at least 3x the cost of the wheel pilot and may have a more involved installation, but is something you can rely on. We cruise short-handed and consider it both a convenience and a safety issue. Our Raymarine/Raytheon below deck pilot is fully integrated with our navigation equipment and has served us faithfully for over 10 yrs.