Your math is off. The closing prices for the commons and warrants were $4.32 and $2.38, respectively.
At $10:
Commons: $10 - $4.32 = $5.68 profit = 131.48%
Warrants: $10 - $3.78 exercise price = $6.22 per warrant, $6.22 - $2.38 = $3.84 profit = 161.34%
At $15:
Commons: $15 - $4.32 = $9.68 profit = 224.07%
Warrants: $15 - $3.78 exercise price = $11.22 per warrant, $11.22 - $2.38 = $8.84 profit = 371.43%
My above math is ignoring any premium on the warrants as well. The reality is that if the commons traded to $10, the warrants would be worth at least $6.22, but would also have a premium attached, so would likely be worth $7.50 - $8.00. So again, it's clear that if you believe the commons are heading much higher, there is far more value in the warrants still.
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