If you are going to be shooting mostly macro, you might want to leave the M52 wide angle wet lens on dry land. I find that the M52 makes it hard to get super close to your subject. I use the M52 when I anticipate a need for real wide angle -- namely, when shooting wrecks, or underwater landscapes, or large pelagics. But for macro, I'd suggest either shooting with no wet lens at all, or buying the Backscatter "air lens" -- which has a narrower field of view, and a smaller dome. In fact, if you are going to only buy one wet lens and you want to do mainly macro, I'd suggest the air lens over the M52.
I also find it helpful to clip a spare mask neoprene/velcro case to my BCD, and to store my wet lenses in the bag when I don't need them for macro.
One word of advice that may save you $$$: if you get into the water with the M52 lens on your camera, keep the neoprene cover on it until you are ready to start shooting, and put the neoprene cover back on before you get back to the shore/boat. That lens scratches easily and cannot be polished. If you nick the top of the dome, it WILL show in your photos/videos, especially when shooting into the sun/surface. When you remove the neoprene cover, just tuck it into the sleeve of your wetsuit.
Also, be mindful if shooting macro with either of the wet lenses not to touch rocks/coral. It's tempting to get super close to your subjects, and to forget as you look through the viewfinder that you have a dome in front of your camera. If your lens makes any contract with rocks/coral, it WILL get nicked.
If, despite all this advice, you do scratch your M52, Backscatter will replace the dome for under $150.