a little off topic...but maybe relevant as an alternative elcheapo option?
Background drivel....
After years of using a Sea & Sea DX-1G (Rich GX100) I hesitantly upgraded to a canon G16 in order to get better macro shots. This was solely based upon G16 140mm equiv versus GX100 70mm equiv. Adding a SubSee +10 wet macro lens to my Ricoh accomplished nothing. It moved the minimum focal point further away which resulted in the same size images.
So I was a little skeptical of the G16 performance. Especially after I purchased it and found that the minimal focus distance at full zoom was around 30cm. Not the 3cm I was used to with my GX100 @ 70mm zoom.
So I went very elcheapo on the housing and bought a Meikon (which I then proceeded to drill a big hole in to mount a Nikonos bulkhead connector so I could connect my wired strobes...another story, but a big reason for my going with the cheapest housing available).
Good news: The G16 and Subsee +10 combo performed very well. Focus distance at maximum zoom was around 4? inches, and it produced a larger subject than my old GX100.
Better news: The elcheapo Meikon housing performed very well. The only noticeable performance difference was the shutter button feel was poor compared to my old sea & sea housing. It was sloppy enough that I often failed to only achieve a half press. A significant number of false shots. No big deal. It also featured a built in 67mm thread port for my macro Subsee lens. Which turned out to be a real pain. I was used to using a ReefNet flip-up adapter on my old housing. Having to screw and unscrew the macro lens sucked. (even my fish spotter divebuddy noticed me wasting time on it). Next project is to construct a flip hinge for the Subsee macro lens.
Other news: The Meikon housing did not provide controls for the front or back dial. But I never needed them, much. I mostly shot in manual mode (1/1000 & F8) and adjusted my strobe output level. Having direct control over aperture would be nice, but not required. Both aperture and shutter could be controlled via an spastic 2 handed dual button press.
Related news: the G16 appears to be a poor candidate for wide angle shots (camera lens design, not a housing issue!). It's lens works backwards compared to my GX100. My GX100 lens is fully extended at wide angle. Hence no issue with the housing vignetting as the lens is closest to the housing port at its wide angle setting. The G16 lens is fully extended at maximum zoom, but retracts for wide angle. Hence the camera causes wide angle vignetting as the lens is retracted from the housing port at wide angle.
Bottom line: Meikon works fine if you do not feel you need front & back dial access.