I've heard that circuit boards are unreliable, is this true?

Some other stairlift companies may tell you " Do NOT buy a stairlift that contains a circuit board. Circuit boards simply do not hold up when they are constantly being vibrated and jarred. " or that circuit boards "... are delicate, highly sensitive to vibration and static electricity, and prone to failure. "

If this was true would they be used in cars, washing machines and other common-place modern electrical goods?

The Acorn stair lift are very reliable, with a phenomenally low breakdown rate. With well over 100,000 lifts installed around the world. We would not use a component that could leave our customers stranded without being able to use the stairs.

So don't believe anybody that tells you circuit boards are unreliable!