That depends on what you want out of the balloon.
For me I want a balloon that is durable enough that it stays stable even when overinflated, and has enough of a neck that you can make it look like a pear or lightbulb. I also like the balloon to feel very smooth and silky when inflated. As for colors, solid pastel colors are the best (especially lavender or sky blue), but I'm fine with just about any color. The only exception is lime green, but that's only because the dyes used to make that color limit elasticity, which makes the balloon blow up smaller than other balloons.
Also, I hate Chinese balloons. They smell AWFUL and are extremely fragile.