The larger 280-310ah cells are by far the most popular. We're partial to the smaller 200/230ah cells because 4 of these cells, a 200a BMS, heating pads, thermostat, active balancer, etc. will all fit inside a plastic Group 24 battery box. Having a portable (40 lb.), standalone 200/230ah battery that can support max c-rates (charge & discharge) down to 0f, is a big plus for us. Two of these will fit inside our truck camper's existing battery compartment (sized for 2 Group 27 batteries) with only some small modifications to the ends of the battery boxes.