i was a little nervous about that too, but its not that dramatic of a taper. the nature of the bridge puts you in that minimal "bathtub" and the incubator offers generous coverage at the head and foot end. its the same length as the jrb uq's and fits perfectly along the entire bottom of the bmbh. just make sure you loosen the shoulder to shoulder shockcord.
in general, i enjoy the way uq's fit the bridge style hmmks more than gathered ends. less fiddle factor. no slippage. set it and forget it.