OmniBlend I and V have the same motor and specifications. The only difference is in the controls, which also results in different visual styles. OmniBlend I has a variable speed dial and pulse button; OmniBlend V has 3 fixed speeds buttons: slow, medium, fast, plus a pulse button. In addition the machine has 3 timer buttons which cycle through the all the speeds and turn off automatically. These are timed at 35, 60 and 90 seconds. The advantage of this is, you press play and walk away.