None of those are truly mixing or mastering monitors, so if by "producing" you mean mixing and mastering music to be sold or shared, none of them is really a great choice. The JBL CSB6 would be the choice I'd make among the options listed, but it's not really up to the task, either,

If by "producing" you mean composing and playing just for your personal enjoyment and listening, then some of them might work okay. I'd be more inclined to like the above-mentiond JBL in that scenario.

At that price level, Polk would be off my list.