I-Pad 4 for me!
I didn't care for the I-Pad mini. There isn't that much difference in weight between the regular and the mini but the large screen with beautiful retina display on my I-Pad 4 is sublime. I am a physician and tend to spend much time looking at radiographs which are fabulous on my regular sized I-Pad.
I also have a Kindle Fire that I use for reading and often travel with both the I-Pad and the Kindle. I know that I can put my books on the I-Pad but even with plenty of storage space (I can't find enough to fill my I-Pad), I prefer the size of the Kindle Fire for reading novels alone. For anything visual, such as medical textbooks, videos or pictures, I am with the I-Pad 4.