You can use an olympus housing with a glass dome or port.
It came off to me that you were implying that using the oly housings and the ports available are optically inferior to the aluminum housings.
I don't think that's the case. Now, those housing have other advantages especially over the PEN housings.
I can't comment on the Meikon housing, but I would suggest that the oly housing solution is closer to the aluminum ones in quality than it is to Meikon.