I just purchased a Helite vest and I see it as inexpensive insurance. It does deter the airflow a bit with my summer jacket, but it's worth it for the added safety. Otherwise it's very comfortable to wear.
It's a bit stifling in the summer months if wearing a heavier summer jacket, such as my Motoport. Also, I noticed after this video was made that the velcro strips up the side can completely tear up a soft helmet underlining, such as what Arai typically uses. Otherwise, it's a solid product.