I have 2 bags I usually carry. My everyday pack is a 5.11 MOAB 10. In my rig (ambulance) I keep a Maxpedition Proteus pack stocked with various IV supplies, bandaging supplies, a CAT tourniquet, Mechanix gloves, and other random supplies and tools. The Proteus is a great tool for me if I have to be out of the rig for a long time. Our first out bags are huge and I find carrying my own pack makes life easier.