Regarding Brim & KOHO:
Well real question is what BMO card you have and what you wanted out of it. If you are currently holding say the BMO Cashback World Elite MasterCard, then ya, I can see why those 2 choices can't replace this card but if you compare it with say the Scotiabank Momentum Visa Infinite, CIBC Dividend Visa Infinite or even the MBNA Rewards World Elite MasterCard, then they can compete.
Really depends on what you're looking for in a card...