I am toying with the idea. I used a similar Tech 21 case on my 5s. Nice grippy case. Doesn't attract lint which I like, it really soaks up impact if you drop it. They're nice cases. I'm waiting to see what the TwelveSouth BookBook for the 6 plus looks like.
I have one and tho it's not the slimmest case it does feel like if protects the phone well. the only i personally don't like is that the buttons are also covered, which makes them a bit harder to press and i may sell here real soon. If do it will be real cheap like around 20.00 shipped. Not sure yet though.