ASDF,
I'm a little late coming to this thread, and it's kind of moot now that you've already ordered, but recently I had a chance to A/B the CBM-170s against my 340s...and surprisingly, preferred the 170s!
If you want the details go here:
http://forum.ecoustics.com/bbs/messages/1/151678.html
Anyways I think you'll be very happy with your purchase, congrats!