There are a million different opinions on tuners. But from the ones you list, I would have to say that the Predator is easy to use and gives you the best bang for your buck. If your towing, it has a solid 40hp towing tune or a 65hp tune that you can tow with. And if you wanna roll the coal when you don't have the trailer hooked up, then you can put the 120hp tune on, and that will let you have a good time. This is the one tuner I have used on a couple trucks, and had very good luck and results with it. The other handheld tuner I would consider on your list is the PPE. Another one that you see a lot of guys use, and have some really good results with. Like others have said, it will run more then twice the price of the Predator, but you can do a lot more with the PPE.
Though, if you wanna have everything at your fingertips, then you would want EFI Live. Everything that everyone has brought up is right on, there really isn't much you can't do with it. It is something that I am looking at getting sometime in the future.