For the nubies asking about IMRs, they don't vape as long for me as e.g. protected AW 2600s. You'd have to be using a 9mm casing or a steel bolt as an atty to actually need the current capability of an IMR. With 1.5 ohm atties, the protected batteries vape just great and offer more protection both on charging and discharging. As to the shape of the discharge curve, it's a personal thing, but they both work fine.