To back up what Des said, 4 of us (Me, Josh, Navid, Chris/Pam) all put on larger (Eibach) front bars between the Crows Tour and Crows Pro (Des had the Corksport larger bar both weekends).
Plus : car is WAY more stable/drivable/confident in slaloms. Especially true in higher speed slaloms. Car is (a lot) less likely to bicycle.
Con : it does wheelspin more, and MIGHT be a negative in sweepers on the clock.
Gut feel is if it were a VERY tight course that was all about 25 MPH digs (i.e. local small lot course), you might want the stock front bar. Otherwise, just accept there will be more wheelspin and the front bar will be faster. On most "National" style courses I've driven, I'd take the bigger front bar.
Other note we found : be sure you have the bar bushings as far towards the REAR of the car as you can before tightening them down. Really helps to have one person tighten while another holds the bar in place (i.e. pushing it towards back of car). Otherwise, the Eibach bar will "clunk" on the subframe. Not an issue with the Corksport as it is bent differently and won't be anywhere close to the subframe.