Which tire has the highest Treadwear (UTQG) in size 305/50R20

It's time to buy new tires for my car, but I want to buy a tire that lasts longer than the original brand, OEM. Which tire has the highest Treadwear in this size 305/50R20?

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600 - Treadwear

 Nitto Terra Grappler G2 All-Terrain Light Truck Radial Tire - UTQG: 600AB - Tire Rating: 0

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520 - Treadwear

 Pirelli Scorpion STR - UTQG: 520AB - Tire Rating: 3.57

 Cooper Zeon LTZ - UTQG: 520AB - Tire Rating: 0

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500 - Treadwear

 Toyo Open Country A/T - UTQG: 500AB - Tire Rating: 4.52

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420 - Treadwear

 Kumho Ecsta STX KL12 - UTQG: 420AA - Tire Rating: 4.5

 Yokohama Parada Spec-X - UTQG: 420AA - Tire Rating: 4.55

 Toyo Proxes ST 2 - UTQG: 420AA - Tire Rating: 4.43

 Nitto NT420S All-Season Tire - UTQG: 420AA - Tire Rating: 0

 Nankang SP-7 - UTQG: 420AAA - Tire Rating: 4.31

 Toyo Proxes ST - UTQG: 420AA - Tire Rating: 4.58

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360 - Treadwear

 Maxxis MA-S2 Marauder II - UTQG: 360AA - Tire Rating: 4.08

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