Originally Posted by
Andeh
No experience with your trail conditions, but have played around with a handful of inserts on lighter casing tires at lighter weight (aiming for sidewall stability & rim protection). The short of it would be that if you're serious about protecting rims, I don't think you can drop your pressure more than maybe 1 psi. I am running EXO+ (old style) with a Tubolight HD insert at very low pressures, but it's for sidewall stability since my local trails aren't rocky. When I go ride somewhere rocky, I wouldn't run anything lighter than DD in the rear, probably with my same insert for piece of mind. I haven't tried DH casing yet, but it's on my list to do this summer.
I personally hate the Aggressor (felt that it doesn't roll that much faster than DHR but brakes and corners far worse). The Dissector does roll much faster than a DHR and still corners ok, but it wears out very very quickly. I start seeing significant wear on a DD MG Dissector in like 9 rides on hardpack. I'd guess rock would just eat up the braking edges and side knobs. I briefly tried an Eliminator T7/T9 and really liked it - it felt like a good midpoint between Dissector and DHR. If I wasn't shallow and cared about running matched tires, I'd run it on the rear. (Don't like the Butcher up front vs. an Assegai, so that's my matchy-matchy hangup. When they finally release the Cannibal, I'll try that with Eliminator.)