.20 is not the best compromise. The word compromise to mean it lays between ideal.

Its just a cal that simply did not off. In sub 12, .177 makes more sense.

.22 hits in FAC or higher cals.

In .177 and .22, you have a huge range if cals and styles with ultra light to ultra heavy that. 20 can't even get close to. If you like .20 and think its a magic cal we'll fine thats your perogative. Select your own level of delusion but .20 inhibits your choices