Do NOT buy ultra thin laptops
Good cooling demands sufficient airflow and a decent amount of cooling surface. Ultra thin laptops do not have room for decent cooling. The fan(s) have to be very thin profile which reduces the amount of air moved for a given fan speed and there is no room for a large cooling surface to be cooled by the airflow.
Any well engineered laptop should sustain continuous heavy use without overheating or excessive fan noise.
Unfortunately the Microsoft Surface laptops are not well engineered.
When you add the difficulty in replacing the battery which is a short life component, only a mug would buy a Microsoft Surface laptop.
Icon for the M$ engineering ===============>