Picked up a set of MIP pucks for my 2.0 last week, previously I had the Tekno driveshafts on it, immediately I could feel a signifigant difference in weight between the 2, but when I ran it... It was too quiet!! Seriously, it sounds like a 2wd or the belt driven AE now!! But it was very smooth, I couldn't tell if it helped acceleration or not, the track was very dry and dusty.
Time will tell when I take it to the indoor tracks, but so far I like them, i'm assuming its being more efficient with the noise level down, more power is being put to the wheels instead of being wasted making all that racket!