I've never done pogies in my truck but I did do herring for many years. the keep alive seemed fine to me. The round sponge that goes around the outside of the pump keeps the scales out of the pump. You just need to clean it now and then , epsecially after you first catch them and there are lots of scales coming off do to the handling. also as stated above , you really want to get the bait fish back into the water in a laundry basket. This not only keeps them alive better but also gives some who have been stressed in the tank a chnace to get reoxigenated and recover.
So that's a vote for Keep alive but i have to say that trying to catch and keep bait alive in your motor vehicle is the single biggest PITA in fishing!
