Barrel length opinion

So I have been going back and forth about getting an ar in 308 for a while. I have mainly been looking at PSAs line up and I was thinking maybe one of their Sabre models. I like the look of the moss green and tan combo ones but it looks like rn all they offer is the 16” barrel ones, though I swear they had longer ones in the past. I know they have some others in 18” and 20” and I was wondering for a general purpose you would choose or so would be. I don’t have a specific purpose for it, just was looking for a general purpose one.

What barrel length would you recommend?