We had one of the square blender jars and decided to try something new.  We are really happy we did.  When we use ice in our drink, the ice doesn't affect the plastic.  It has stayed new and clean like the day we bought it.  Our smoothies whip up like milk shakes.  We are looking to get another one.  We have also made peanut butter and don't need to add any oil.  The same with Almond Butter.