if you are sure of that you can’t go better than that. I have 3 for all my saxophones (these days I have a curved soprano)
I just bought a Protec baritone case with the accessory rucksack straps. I haven't tried falling down stairs with it on my back but it seems pretty solid and protective.
I use a Protec soprano case for my EWI. I don't have any kind of soprano to try in it, but I'd be astonished if it wasn't a good fit for a one-piece.