I love (not without reservations, though) the Sculpt Ergonomic Desktop keyboard and mouse design, I already had three sets and wanted to buy another one, but...
That's right, they don't last more than a couple of years of copy editing and to add insult to injury, those three were barely acceptable after... having returned right away even more than that because they were all more or less defective.
It was either some important function button (since these are not real keys) not working or virtually non-existent wireless transmission, or a faulty mouse button (left, then right), or - no surprise here - the space key which was really hard to press correctly. Even in those that I kept the space key was a little spotty and the mouse Windows key was spotty at best (I don't use it, fortunately).
None of those seven or so sets should have passed the quality check. Well, there were at least eight in total since one had been clearly returned by another hapless user so I didn't even try it.
When the last one, that I use currently, gives up I'm going to try Perixx PERIBOARD-335. It's not equally ergonomic but it sports a full set of low-profile mechanical switches. Enough of this membrane crap and mouses permanently tied to keyboards.