Used to work ok on my mini yes, manged to get from "dangerously hot" down to "hotter than I want but liveble" and they are a good test (highly tuned engine and inefficient side mounted rad)

Ive got a few things I want to use it for, and some of them are quite large volume (nova is 19 litres water capacity for the charge cooler system for example) so could do with some sort of pack of half a dozen or something if possible rather than having to pay full retail.