Does anyone own a pair of Apple Bottoms jeans? I heard they make your derriere look fantastic

I've been looking at them on eBay, and the sizing/measurements seemed odd to me. A size 1/2 has a 12" waist, and size 3/4 has a 13.5" waist (measurement across the top). The measurements seem really small to me (I usually wear size 0 or 24, 14" across), so I'm wondering which size would fit me the best? Or perhaps the jeans are REALLY stretchy?

So here's my question... Are they true to size or do you need to size up?