I really like the second one of the Seahorse. Keep in mind that somewhere down the road, you might want to change it up or add some color to it so the second one would be much easier to manipulate. Are you going with black and gray like the picture?
The less skin in the area that you're going to tattoo, the more painful it is. It's not a horrible pain and your skin gets used to it after a bit but that might be something to keep in mind while you're deciding where on your body to put it. Top of foot, ankle, hand etc.. will be a bit more unpleasant and also really sensitive areas like ribs, stomach.
Good luck and keep us posted.
Animal testing is a terrible idea; they get all nervous and give the wrong answers.