A sweet lady at the church I attended growing up used to make these for potlucks and church dinners. She once gave me the recipe on a card, which I've long since misplaced, but I had copied the recipe into another cookbook and have made it many times. Every time I take these bars somewhere, people ask for the recipe. I like to cut the sugar down by at least 1/4 cup, because the pineapple is sweet enough, and I've always made these with real butter. Quick oats or old-fashioned will work, but the old-fashioned does make it a little more challenging to press the crust into the pan. I intend to try a mixture of the two at some point, but haven't ever done it. These would be great for a bake sale, potluck, or gifts. The crust does tend to be a little soft, so I'd be sure to package with something firm underneath, rather than just wrapping in plastic. I've seen other recipes that add nuts, coconut, etc. I'm sure that would be great as well, but this is just the basic, buttery, oatmeal and brown sugar crust and topping. Yum.