Another big rider here (215 lbs), and a fairly aggressive rider, and on a hardtail. My back wheel hates me.
I’ve been running Nukeproof ARDs front and back for about a month and a half now, and I think they’re worth the price and weight. They feel very firm in the hand; I can’t really compress them much with my fingers. Installation is more difficult than a tire with no insert, but seems easier than some of the horror stories I’ve heard about Cushcore. The main difficulty is getting an old tire off the rim, since the shape of the insert supports the tire bead quite well. On the trail they seem to damp small chatter a little bit, although a softer insert would likely do more in his regard. I have been able to run lower tire pressures front and back. It’s only a few psi, but it’s enough to make a difference. On hard hits I can sometimes feel the insert bottom out on a rock or root, but it is less harsh than the rim hitting by itself. I just spent a day at my local bike park and my rear tire was really lower than it should have been for some of those trails, and I definitely bottomed out my rim a few times, but I don’t think I dented it at all. They also support the tire bead and sidewalls pretty well, so it would be much harder to burp a tire under hard cornering. One thing to note is that they fit on the rim rather loosely; this makes installation easier, but it allows the insert to rattle against the tire sidewalls a little bit. It isn’t too loud, but it is noticeable.
Another thing to consider is longevity. I just swapped out my rear tire and the insert seemed pretty much brand new, except for a minor deformation in one spot. I don’t know how they’ll hold up long-term, but I expect them to last a good while. Only time will tell. NSMB did a good article on the pros and cons here.
And for reference, I’ve had the inserts in the following tires: F: WTB Vigilante 27.5 x 2.5 tough/high grip, e*thirteen LG1+ 27.5 x 2.35. R: WTB Vigilante 27.5 x 2.5 tough/high grip, Maxxis High Roller II 27.5 x 2.5 WT Double Down 3C Maxxterra. All mounted on Stan’s Flow MK3 wheels (29mm internal width).