The Vaporesso XROS 4 is the full-size version in the XROS 4 line, built around the newer COREX 2.0 coil. The point of that coil is to keep the flavour richer deeper into a pod's life and to make the pod last longer before it starts tasting flat, which is the usual weak spot with pod vaping. It stays in the XROS pod family, so the pods are easy to find and quick to swap, and refilling is simple. The draw suits a mouth-to-lung style, and the larger body over the Nano and Mini generally means a bigger battery and longer use between charges. It's a solid everyday pod for someone who already gets on with the XROS line and wants the updated coil, particularly if pod lifespan and steady flavour matter to you.