Great honest review of plus tire inserts.  Combined with plus and fat tires, it's a game changer on hard riding and technical terrain.  

I gotta say though I really dig the Vittoria Air Liners in my regular, plus, and fat tires.  Like the CC, they offer different widths for your application. They cost less at about $55ea and weigh significantly less as well.  The amount of stability they add at lowww psi is unreal and I won't ride plus or fat without them again.  Install is easier than the CushCore in my experience, but it's similar that you have to get the tire toward the center channel to get it to fit easier.  WTB tires are much tighter fitting, maybe too tight, than the excellent Bontragers I've been running.  Wish they made a 27.5x3.0 XR3,4,5.  I've found that you can much more reliably run a light casing tire with the Airliners without worrying about punctures and the insert provides all the damping you need.  It can stretch after the first install but it's easy to trim it to fit right around the rim again at your next tire change.

One last thing, I recently had a flat due to my tubeless tape on the rim finally failing after yet another tire swap (I have a tire addiction problem) and it was a revelation to be able to just pedal easy and roll back out to the trailhead without any tire, rim, or insert damage.  Fixing flats trailside is a thing of the past.