Pure sine wave inverter suggestions?

Regardless if we call DC to DC converter an inverter, or not, Wikipedia gives them typical efficiency 75% to 98%, where I believe 98% applies t step-down converters. Meaning they don't have to be more efficient than inverter + converter combo.
Owners of those report them getting really hot, what not only raise efficiency questions, but also brings additional hassle about finding placement with good ventilation in stuffed camper .