Are you driving your prius while this is being serviced? The Insight is a completely different beat to drive when my Enginer kit poops out and Id rather park it and drive my Suzuki or a rental car as its soo unpredictable in its acceleration and IMA behavior.
With the kit I am at 90-100% charge and the car is always assist happy. Without it it will regen vs assist when I pull away from a light, go up a grade, etc. Owning this hybrid Ive seen the car do a lot of things against what you are told hybrids do. Ive see it assist going down hill and regen going up.
The plug in kit eliminates all that foolishness.