I have all three and I vote Ina 2. I like Tiger when I'm in the mood for something large (but it basically gives no clit stimulation), and Delight is nice when I'm in the right kind of mood for just G-spot stim (again, for me, it doesn't hit my clit), but Ina 2 is the one I use most often. It's a more reliable, easy G-spot + clit orgasm-inducer.
If it were on the list I would pick the Jopen Vr7, but the reason I use it most is because I prefer rotating G-spot stimulation, and the clit arm is more powerful than Ina 2.
I think Ina 2 has to fit you just right for you to love it. I have a pretty shallow G-spot and Ina 2 just hits it, and I have to push the clit arm around a little to get it in the right place.