The M-91ED competed head to head with the Pickering XV/15 400E, and had a slight edge sonically. The Pickering however was a workhorse that could stand a considerable amount of abuse that would have destroyed the Shure, and that's why all of us at Lafayette Radio at the time, sold the Pickering instead of the Shure. And our customers actually liked the idea of the brush: in my experience, it was almost never the customer who didn't like the brush, but the audio salesman who pushed his own beliefs on the customer.