Nutribullet has historically dominated the single-serve, bullet blender market, and their latest release, the Nutribullet Ultra is by far the best model in their offering. It's by far the most powerful personal blender on the market, plus it looks beautiful too.
I already own and use a different Nutribullet (the Pro 900) every day. Before the Nutribullet Ultra, I thought my Pro 900 was one of the best blenders on the market. However, after testing the quieter, more powerful, touchscreen Ultra, it'll be tough to go back to anything else.
