As a general rule, more coils equal better quality innerspring, but not all coils are made the same. To determine quality of the coil we need to consider factors like type of steel used, size of the coil and gauge of the coil. Obviously most of the time you won’t be able to find all these attributes even though they should be provided to you by all manufacturers to help you make a good decision.
Type of steel used in coils production is obviously very important in determining the durability of the coils and their ability to keep their shape and spring for a certain time. It is nearly impossible to find this information about majority of products out there. Lately, a few brands started to advertise their use of titanium or carbon in their springs. Don’t get fooled by their marketing. They use only a fraction of these high-end metals in the steel where it doesn’t have any impact on it’s quality.
Size of the coil is another attribute that determines the quality of the whole innerspring. The coils are made from the steel wires. Longer wire allows for a taller coil with more compacted turns. Depending on the gauge, taller coils with more turns will provide better support and last longer.
Gauge of the coil is a measurement of diameter/thickness of the wire the coil was made from. The lower the number, the thicker the coil. Coil gauge varies from product to product and generally it correlates with coil count. Typically you fit less thicker coils in the same size mattress. The gauge can fluctuate from under 13 for a very firm coil to above 16 for a very soft coil. When comparing different gauges, make sure the coil system and coil count is similar.