They save to a server so if you are in the same area they should be able to get to it. But, they can get the current setup from your hearing aids anyway.
Depending on the brand (not sure who has what) there is a dome called a tulip dome. It has two flaps that overlap slightly. It is a little bigger than a regular dome and conforms to the size of your canal. I had that and loved it. It has better feedback control but is not occluding, and they are very comfortable. I couldn’t tell I was wearing anything.
I have heard the limit for open fit was around 25 to 40 loss at 500 Hz, and it depends on how much amplification you need in the high tones. I used the tulips with my hearing test results below. My hearing is a little worse now so I’ve gone to a custom mold. It is comfortable also (but the tulips are better) and the mold has a select-a-vent thing where it is vented with a large hole and they give you inserts that fit in the big hole and have different size holes. I tried the different inserts until I found the largest one that would not give me too much feedback.