I’ve just invested in that exact setup after running out of battery twice around the 15 mile mark. I am a big guy and was riding steep technical terrain in cold weather, but still wanted more range than that (after all, that’s one of the main reasons I bought an eMTB).
On a Ride in the Cheviots with @The Hodge I managed only 16 mile range in cold wet and windy conditions….
Battery replaced under warranty!