#2 Can this start from room temperature water to warmer water or just only start from hot to prevent turning cool?
The COSORI 17 oz MUG (2 pack), available on Amazon, has a flat bottom and a lid and it works excellent with this Cosori mug warmer .... See my detail review of this warmer. I use it multiple times per day and yes (with this mug) it will easily warm room temperature liquid to be piping hot ... The digital display shows the temperature of the warming surface, so you can watch the warmer heat up. Awesome feature.
The key is having a flat bottom mug with a lid.