Can't remember the application, but I would like to offer this information.
I would choose MA first if the speakers were to be used full-range, without a sub. They sound the best out of the three for that application. When you add a sub, I feel they are lacking. They are too smooth, and seem to be beaten by the other two.
Now, the fun part. When a sub is added, this is where the B&W shine for me. If you audition a speaker by itself, you may feel it is to forward, or harsh. But, this changes drastically when the sub is added.
The Polks are in the middle. They have the strong, forward mid-range, with the mild tweets.