i dont see why you would want 15" + wheels on a mini... the proportions look completely off... the handling would be compromised...
I agree with the proportion - not so much with the handling. If done right, it handels better than any Mini will ever do. But that needs much much brain grease, $$$, time, skills and effort.
LaYaSWyrE2M
I had a ride in that beast - it's stuning how good it works! Realy superb... As far as I know Rover 114 suspension parts play a role there...
However: in the end I totaly agree with you!

If you just bolt 15" wheels onto a Mini it will neither work nor look pretty. And I doubt the person who's asking (NO offense by any means!!) will afford such radikal modifications to make it work well. If it's for a show car - go on. Each to theyr own