I would think my number 1 complaint about the driving experience was the occasional (but not predictable) incredible lag between pressing the accelerator and the car going faster and the ridiculous over-revving when I presume the car got confused about what gear it thought I should be in.
I've never seen the lag (much less "incredible") in any model I've known.
I've indeed seen the over-revving sometimes. That said, how is the over-revving any issue compared to the whole not having to even worry about manual gear shifting benefit?
It's like going to the US on a boat, because airplane food is bad. Yes, it might be, but it misses the whole point of getting there faster, easier, safer and with less concerns.
Check out a Smart fortwo on car2go sometime and be amazed :)
It feels somewhat counter-intuitive as normally you press the pedal to speed up, but when going uphill you sometimes have to really step on it just to maintain speed.
"second worst driving experience" has nothing quantifiable.