At a certain point your best bet is really to profile the two approaches to see which performs better. But if you are starting out with nothing built and only

At a certain point your best bet is really to profile the two approaches to see which performs better. But if you are starting out with nothing built and only have time to write one, you can't really go wrong by going with the one with the better Big O. If it's the same, coin toss I guess. :)