The clips under my kitchen sink are terrible. It's impossible to get them tight, and as result it's hard to keep the top caulked, and I now have water damage. The clips in question were from a Realtor special renovation, and look like:
The head goes into a track that's part of the sink:
I think it's called a U-Channel sink.
The problems include that the bottom screwdriver slot strips, the screws are hard to turn, and the tighter you get them the more the entire thing wants to tilt away from vertical. I've tried to get this right a half dozen times, and the best I do is get half the clips to actually bite.