I have used them frequently on light fixtures, espically in commercial installs where i've wired 200+ 2x4 fixtures. I use them now in my own business, however I have to agree with 1000BaseT, it is a hard conceptual leap to make a splice you know is going to carry a large current or a 3 wire neutral and not see the splice is nice and tight.
I'm sure I'll cross that hurdle at some point, but for now I use them on fixtures and low load splices.
