hesitates and jerks while accelerating

It is my daughter's car. We got it last August. She noticed that it seemed to drop out when accelerating. It seemed particularly sluggish in the low gears. After I used her vehicle for a week in May, I was livid. They tried the "low oil" excuse but then they got it to reproduce the issue! It is terrible. Very lower power and it hesitates and jerks and seems like it misses or just stops at times. The dealer has been very good and did test after test under Chrysler's guidance and supposedly even brought out an engineer from Chrysler, but the performance problems cannot be fixed. There are several complaints and I am hoping that they come out with a fix/update soon. I would think this type of performance would be embarrassing to them, but I guess they already got paid, right? Discouraging to pay so much and have it run crappy. I am adding complaints every place that I can and I am calling Chrysler Care. Eventually might have to do Arbitration or invoke our State's Lemon Law.