I had E load rating KO2s on my Jeep TJ for 10 years and I loved them. However, my tire shop warned me of vibration issues when I wanted them on the 4runner and they recommended Coopers. I didn't listen. They also put 50psi on the tires which I thought was wrong and aired them down to 32psi for 2 years - until I learnt from this forum and verified with BF Goodrich that 45 to 50 is indeed the correct pressure for 275/70R/17 E load.
An offroad outing went wrong and had the body and wheels badly scratched/dented so I bought 4 OEM tires/wheels (Dueler 265s) at Kijiji. The plan was to swap out the wheels but I ended up having the duelers for summer commute and have the KO2 for winter and offroading.
What I found:
Dueler 265 weighs 35lbs; KO2 275 weighs 55lbs. It's exhausting at my age to put on the KO2s.
With the Dueler I'm saving at least 10% on fuel (15% when I had wrong/low psi on the KO2s).
No, I don't recommend the Dueler. It's just for your reference only.