For my MARS work, I generally use 3 antennas:
A Carolina Windom 160 at 35 feet
A Carolina Windom 80 at 60-65 feet
A 40m delta loop.
I do use a tuner, and I'm told that I have a good signal on most of the nets I participate in, with the exception of a few around 40m, where none of my antennas are really great for high-angle radiation (although selecting a different feed point for the delta loop would probably fix that concern).
My CW160 is OK on every frequency I've tried except for a few (AFAIK) uncommon low frequencies. The only time I have problems with the local net near 160m is when the cat has been playing with the grounding straps. However, my CW160 is a few dB down from the CW80 on several frequencies.
For quite a while, I only had the CW80, and it remains my preferred antenna for the frequencies I'm most active on. However, a desire to improve my station lead to the sprouting of an antenna farm.
If you do go with the unbalanced antennas like the CW's, however, make sure you have good RF grounding, and perhaps keep a good supply of ferrite beads on hand just in case.
Personally, I think that if you have the space for a CW160, you would do well to consider going for it rather than the B&W160. The B&W may have the advantage of being broadband enough to avoid needing a tuner, but its broadband nature comes at the expense of efficiency. You'll likely be anywhere from "not much worse" to "quite a bit louder" with the CW than the B&W, depending on the specific frequency.
Of course, if you have the space for more than one antenna...that would be even better.