You don't need the 180. You won't miss anything with the 160v4. You can also get that in an in-wall.
As for your in-wall constraint, poor you!
Thanks. 180 is shorter, which allows it to fit better below my tv. I've only got about 60" of vertical to work with to fit the tv stand, center channel, and tv.
Is the 180 a bad match for the rest of the setup?