raise it preflop

you aren't always going to flop a boat, but your opponents who limp in after you may hit something that kills your big pp that you will have a hard time letting go.

If you do raise it pf, you will still probably get the limper calling, and you will have an easier time getting his chips in the pot when you like the flop because the pot is bigger, and he is more likely to stay in because he thinks those are 'his' chips he has put in there.