True what you say about the potential lower profile with a lesser known brand or one that is not obviously a luxury brand. I like that a lot, too. My idea about having something from a rarer brand was rather that I like the exclusivity. So when you go to the real refined circle you find brands that are quite rarely seen but still offer excellent quality and are actually on the exclusive side also in terms of price. It's like anybody can buy a Louis Vuitton satchel but few people walk around with hand-made English saddle leather satchels that are about as expensive but still better quality. It's almost the same thing for Tumi and Andiamo. Andiamo is as expensive and high quality as Tumi or perhaps even more so but hardly anybody knows them and you see very few of them around. It is less conspicuous for the untrained eye but will be tell-tale to the initiated. Just one form of snobbery.
As for theft protection I am not sure. Common sense has it that Rimowa, Tumi and Vuitton would scream steal me. OTOH you'd think that even the common luggage thief would do a little bit of research to maximize his gains and minimize his risks of stealing a dud. So someone only half way in his right mind would go online and check out the expensive luggage brands. So they'd know also Boyt and Andiamo, I suppose.
It might be more helpful to have a bag that really stands out and calls attention to it. Everybody will notice the person accompanied by that bag so to say. Thus making an easy escape is difficult. But that's another thread obviously and we've had that discussion already.
Till