In my opinion we should not abuse the B&W in underwater photography.
It's my opinion that we actually abuse vibrant colours, detracting from the shapes and compositions that are also unique to the world accessible to divers.
That was my reason to include the imperfect shot that heads this thread: the shape and composition seem strong to me, despite the mirky conditions and the combination of odd optics, a torch rather than a strobe and high ISO. Strong enough to explore in a monochromatic reproduction that hasn't, perhaps, come off as well as I had hoped.
I've used Inon Z240s and, in darker water, they are fine. There is a learning curve, however, and the trick is balancing the strobe light against the ambient light: most of the wreck is lit by the sun, not by the strobes. For wide-angle work you either highlight a small area with one strobe, or use two on longer arms to spread out the light. The strobes need to be well behind the handles of the housing to reduce backscatter.
I would recommend Martin Edge's book (and Alex Mustard's on-line articles) for advice, but it's still several dives' work to begin to get the strobes right.
In bright conditions Inons are under-powered and it's hard to balance the light.
Even under perfect conditions wrecks make for challenging subjects: