I thought it was more about the general question of differences. Sorry if I missed the point. I’m also not too much into the other project to be able to speak about differences in detail.
I thought the other device also runs Mobian, just with an Android Kernel. Or what did you mean previously?
I strong prefer using an Androide device than be a crazy capricious person changing batteries on something that is not properly done. I love Librem5, i love Purism, i love Gnu too but i just waiting the right moment to using L5+Gnu OS. At the moment i using Xperia Murray+Sailfish OS it is a delicious combination.
I use a 10,000 mAh power bank throughout the day to keep the Librem 5 fully charged at the moment, and I turn it off when not in use.