This may sound crazy, but after playing the game for nearly 5 years, I've never got to experience any of the DLC towns (yet)... Either due to lack of money or lack of time because of college to get into any of the expansions, I pretty much have only casually played through our three good ole' default maps.
Never been too much of a fan of Oasis Springs, perhaps I never really found much appeal in the whole desert location; while Newcrest is quite a fun concept as a DIY free map, my style of playing resulted in it remaining fairly empty to date, and so when I move an household to there, not always the surroundings seem to have a proper lived-in feel to it. Willow Creek, on the flip side, feels just like a cozy area to live, no matter if you're playing with a starter home, rubbing shoulders with the Goths or checking the town from above from one of the largest properties. It has always reminded me so much of the default city from the OG Sims 1 that I've dedicated so much time playing during my youth - perhaps that's where the appeal comes from!
I found it pretty interesting how the default maps seem to get little love these days, from what I can conclude from the poll. I guess with the college vacation finally approaching, I shall definitely pick up at last one or two DLCs to enjoy what I've been missing out. ;)