The folks at CHOW and Modernist Cuisine tested and developed software to test heat conduction through different types of saucepans so you don't have to, and the results are actually surprising. Before reaching for that expensive copper saucepan, think twice: a more affordable but thicker steel saucepan is a better buy.
Modernist Cuisine's Scott Heimendinger explains why above, but the lowdown is this: copper saucepans transmit heat from the burner to your food faster. But when it comes to even cooking and maintaining regular heating without hot spots around your saucepan, it's the thickness of your saucepan — not its material — that matters most. A thicker steel or aluminium saucepan will do a much better job than a copper one, which are usually thinner.
Scott goes on to explain the delicate dance between conduction (heat transfer from the burner to the saucepan) and convection (heat loss to the air) in the video above. He even offers up a bonus tip to keep your saucepan extra hot and even: visit a metal shop and get an aluminium block to put over your burner. If that's too much for you, just reach for a thicker stainless steel or non-stick saucepan. Your food will thank you.