When I flop a straight in a six handed pot I like to lead into big fields. I dont like checking, since the flop could get checked around which would be a disaster, and if a late positon guy bets you really dont want to checkraise and force the whole field to call 2 small bets.

By betting this flop you encourage all kinds of hands to call drawing close to dead, like overcard draws, and one pair draws. This dead money is very valuable, and when you check this flop you risk losing all those loose flop calls if it gets checked around. So I think you should take the bet/3bet line in this situation.

I know there is no such thing as always or never in poker, but if you never slowplayed a straight in a 6 handed pot, you would be playing pretty close to an optimal strategy.