The usability is nowhere near acceptable with a cellphone for daily usage with either or those options, or with the native client in Waydroid because it's not persistent if Waydroid is closed.
Signal with anything other than the official client sucks ass. I know, I tried.
And that's without mentioning that you still need to have the "master" Signal client running on an Android cellphone, which defeats the purpose if you want to ditch Android.