I've taken my car to Iffy Lube in the past and not have any trouble. That said, I would go to them as a last resort. They are the least likely to care about doing the job right. If you trust your dealership, take it there. Many charge a little more, but much more likely to do a better job and use better filters. If you live close to one, may even be good to ask them to throw in a few free oil changes with purchase.
That said, the key is the attitude of the person doing the work no matter where you take it. That is why it is often best to do it yourself once you've been shown how to do it correctly. In some cars the filter is hard to reach, but I understand you don't even have to lift the Elantra to do this (though it might help to lift it a few inches.)