I drove a few laps with a regular shorty too. The only time I really noticed a difference was on a downhill section of the track that goes into a sharp turn. The car felt a little light in the rear.
My car is weighing in at 1633 with the LCG pack that weighs a good 60g less than a regular shorty. I don't know how I'm going to axe ~175g without one for running stock.