This is where it starts to get subjective, but changing one part of the toolkit can have a huge effect on the quality of the assistant. For example I tried GPT 4.1 instead of Claude 4 recently and it took my setup from improving my productivity by 3-5x on coding tasks to, like, 0.5x. I can't point to a specific change other than tasks went from being done in 5 minutes if back and forth to being only partly done in 15 minutes.

I haven't used VSC in a year or Cursor at all, but I hear similar things from colleagues.