Which tire has the highest Treadwear (UTQG) in size 255/60R17

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 255/60R17?

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640 - Treadwear

 Nitto NT421Q Premier All-Season Crossover - UTQG: 640AA - Tire Rating: 0

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600 - Treadwear

 Yokohama Geolandar SUV G055 - UTQG: 600BA - Tire Rating: 0

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520 - Treadwear

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

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500 - Treadwear

 Kumho Solus KL21 - UTQG: 500AA - Tire Rating: 4.52

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480 - Treadwear

 Nankang SP-5 - UTQG: 480AA - Tire Rating: 4

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420 - Treadwear

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

 Marshal Matrac STX KL12 - UTQG: 420AA - Tire Rating: 4.66

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400 - Treadwear

 Pirelli Scorpion Zero - UTQG: 400AA - Tire Rating: 3.53

 Sunitrac Focus 9000 - UTQG: 400AA - Tire Rating: 4.32

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360 - Treadwear

 Falken Ziex ZE-912 - UTQG: 360AA - Tire Rating: 4.02

 Continental Conti4x4Contact - UTQG: 360AA - Tire Rating: 3.94

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320 - Treadwear

 Marshal Matrac X3 KL17 - UTQG: 320AAA - Tire Rating: 4.54

 Yokohama Advan ST - UTQG: 320AAA - Tire Rating: 4.55

 Kumho Ecsta X3 KL17 - UTQG: 320AAA - Tire Rating: 4.63

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