Yes I had a look at it, I haven't tried e5-mistral-7b-instruct yet but I'll definitely give it a go.
Is there such a leaderboard only focused on retrieval by any chance? I haven't found one so far
see the retrieval tab
they actually have custom prompts for each dataset being tested.
Question would be, if you haven't seen the task before, what is a good prompt to prepend for your task?
IMO e5-mistral is overfit to MTEB