Big Agnes Copper Spur HV UL2 earns the edge for dedicated backpackers who prioritize shaving every ounce, beating the REI by 1.5 lbs while matching floor area and adding dual vestibules. The REI Co-op Half Dome SL 2 counters with stronger floor fabric and lower cost, making it the pick for car campers or those prioritizing durability over minimal weight. Both score well on real-world reviews fr...