The thinnest cases we looked at include the Air Skin and the Thin Fit. The Air Skin is the thinnest case Spigen makes, and it's really just designed to keep the iPhone safe from scratches. It's not going to offer much protection when dropped, and it's not very sturdy - ours broke.
Spigen's Liquid Crystal TPU case is slightly thicker, but it offers a lot more protection than the two thinnest cases. And it's clear, so it's a great way to show off the new Rose Gold iPhone. When it comes to thicker, more protective cases that still won't overwhelm a device, Spigen's got the Rugged Capsule and the Ultra Hybrid.
There's also a line of two-piece cases, and our favorite of these was the Neo Hybrid, which we thought had the cleanest look of all the Spigen cases. It offers a good compromise between a streamlined look and protection.
For the maximum amount of protection, Spigen has the Slim Armor and the Tough Armor, Spigen's thickest, toughest cases. These are much bulkier than the other cases Spigen offers, and we weren't a fan of the kickstand, which we found tough to deploy.
All of Spigen's iPhone 6s and 6s Plus can be purchased from the Spigen website. Prices range from $14.99 to $34.99.