Carp are good to eat. If you clean them right. I've had carp several times, some good, some well...not so good.
Of the carp species, commons like you're holding, are my least favorite.That and the fact that we shoot way more than we could eatis why I eat most of the carp I shoot only after they've been turned into tomatoes or sweet corn...
Kudos to those who actually eat most of the fish they take. (Like Fishhunter) For us it's just not possible.
Either way, just getting them out of the waterway is a benefit. We never release them on purpose.