The Ariya is only slightly larger, inside for (at a minimum) $10,000 more dollars.
45.8 ft³
Cargo Volume to Seat 1 (Kona)
59.7 ft³
Cargo Volume to Seat 1 (Ariya )
The Ariya has considerably more rear legroom than the Kona, which is a plus. The Kona has less bulk to lug around, and similar power output.
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While I would argue that no other legacy car maker has Nissan's experience, buying a first model year of *any* car is sketchy.