Revel B 15 sub,crossover question

Hi, I am looking into adding either a pair of Revel B 15's or sub 30's to my system,but I would like to know if anybody has any feedback about the hi pass crossover does it do a good job,meaning do the main speakers still image well no loss of mids or highs,and were you happy with the hi pass on either of the subs.

Thanks Mike.
I'm using a pair of Sub 30s. The high pass filter works quite well. The addition brought my system up a couple of levels. I'm told it is better than the B-15s.
I'm extremely happy with a single B15. I'm running Revel M-20 monitors on good stands, and the clarity and imaging are world class. Also the equalised bass integrates seamlessly with the main speakers. Highly, Highly recommended.
I would set the Revel B15 subs to use a second preamp out instead of the high pass filters. I would rather have less in my speaker connections.
I have wood floors on pier and beam. My original down firing sub caused more rattles at lower volumes than the front firing B15s. I started with one B15 and then added the second one. Two are better than one. I use my B15s in a HT setup with 4 M-20 and 1 C30 center channel. The B15s and the M20s work very well together.