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The photo shows three Tamiya kits together. (The $15 Tank track set, the $10 base plate and the $18 dual motor kit)
CD for size comparison. I have found that the combination of gearing and tracks in this package is quite powerful and can scramble over most things its own height (height of the tracks) or even higher if it can get grip.
Don't worry if the motor end looks a bit heavy, Everything is configurable and I moved the small center wheels around to even things out