Great question! I have both cards and I have recently started trying to use my platinum for gas/grocery/restaurant and my regular for everything else. I had been using only my platinum but I still had rewards on the other that were under $10 so trying to boost that up so I can make the transfer while not losing my 2% from the chosen places. Last night I got gas at BJ's so I used my 2% card then went in to get a few things and couldn't decide which card to use.