Magnetic adapters for wet lenses

[LeeCat]

I want to find out from the public about magnetic adapters for wet lenses, for example: Howshot M67 Magnetic Lens Mount with Lock or like this: US $35.0 |NiteScuba M67 Magnetic Mount with Lock for macro wide angle fisheye lens adapter filter holder underwater camera housing-in Photo Studio Accessories from Consumer Electronics on Aliexpress.com | Alibaba Group

How reliable is such an adapter?
Does it provide good axial alignment between the main lens and the wet lens?
How significant is the change in the distance between the main lens and the wet lens in terms of working distance and image quality?

 

[Barmaglot]

I used the Howshot one with a Sony A6300/16-50mm in a Meikon housing and their wet dome. It has a flange ensuring the correct axial alignment, and magnets' hold is quite secure. Haven't observed any effect on image quality, but I haven't tried it with a 'real' lens, neither wide nor close-up.