Hmmm... I really like the Leopard 1, but since I already got one.
I think I'll go with the Japanese Type-10.
Just because it would be unique for North America, plus I like the detailing on it. The Challenger and T-55 are a close second though.
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HL Panzer III | HL Tiger | HL Jagdpanther | HL Panther | Mato Sherman
Hooben Elefant | HL Pershing | HL Bergepanzer IV | Tamiya Leopard 1A | WSN T-34
HL "Golden" Pan-Tiger | M16 Halftrack | HL Panzer IV | Tamiya KV-1 | Tamiya Tiger