I think the Oticon OPN BTE 13 PP (Power PLus?) will be available very soon. It’s been announced recently already (see both threads below that talk about it). Maybe by early May you can get your hands on it. Check with your audi.
I think the OPN BTE 13 PP will probably work better for you compared to the regular OPN1 with the 105db receiver based on your severe hearing loss if you can wait. Or take advantage of the trial period to try out the OPN1 with 105db receiver first while waiting for the BTE 13 PP to become available, then try the BTE 13 PP next to see if you may like it better.
As far as speech clarity, the OPN does have pretty good speech clarity with their new way of doing noise removal around speech. However, its design around the new “open” paradigm means that you will hear a lot more sounds around you and will have to deal with it and train your brain hearing to learn to focus on what you want to hear and ignore the rest, which may take a bit of time getting used to, especially given your severe loss. It’s not a bad thing (I actually think the “open” paradigm is a good thing), but it may need a bit of time getting used to.
With the BTE 13 PP, you’ll also get their new technology called Speech Rescue which will move some of the high frequency parts of speech down to the lower range where people have better hearing in. Unfortunately I don’t know how much Speech Rescue can help with your case because your loss is pretty flat across the board. But at least it’s there, and not only will it be built-into the BTE 13 PP, the regular OPNs will also get it via a new firmware update as well when the update becomes available.