My experience is based on 4 keyboards that we have at home. Apart from the conveniences that an optical interface provides (view, upgrades, etc.), these keyboards are difficult to use and unreliable.
Initially, the touch is not sensitive (it requires a lot of pressure) and you end up pressing somewhere else. Beyond that, they are particularly sensitive. In the span of 3 years, 4 of them have broken. Two of them for the second time! Fortunately, the first ones were still under warranty.
Now we are replacing them with the TM70, which are bigger, more user-friendly, and more reliable.