All the Echo's you named are good. I am very happy with an Echo 1 and my cousin has one to and he says he likes his alot too. The all go pretty much 350 FPS, and I've let people try out my gun that is a M4, and my cousins M16 VN and they are amazed that its such a good gun for the price right out of the box.
If you want range get the M16, if not then get M4 or G36C. Pretty much its all about what you think looks cool to you.