ANDREW McLauchlin wrote an answer about Mammut Borah DLX Approach Shoe - Men's on August 25, 2011
I switched my pair of Cirque pros for boulder x's and used them on a trip to canyon lands. I blew through the boulder x's in less than two weeks using them in slot canyons every day. The sticky rubber was great but way too soft to last very long. Also the leather splits along the top of the toe rand. I would go with something other than the boulder x.