KAYSCASE ArmorBox Cover
These last two are for those who want extreme protection for the LG G3. The KAYSCASE ArmorBox cover offers an extremely durable and thick protective case and cover, yet also has a belt-clip for those wanting that feature. Many cases have dropped that option, but this is one that offers it at a decent price.
Basically this offers a drop resistant TPU interior and a hard polycarbonate outer shell for dual-layer protection like Spigen. However they aren't nearly as thin as the Spigen options, and possibly more durable. Add in the belt clip and you'll get the KAYSCASE ArmorBox in 5 different colors starting at $11.95 from Amazon.