My MIL went on the Britax fit finder and it said the renaissance was OK. She then went to Halfords for a physical fit where the fitter told her that she wouldn't even bother trying as she did one recently and knows that it does not fit correctly - apparently the seat is too loose. I've told her to go elsewhere and double check.
But in the meantime, does anyone have a Mini One and what group 1 do you have?