I've got a group of people from work going to Willow Springs in the next couple months and I was invited. My TL was stock for many miles but I started the upgrades immediately after the talk of Willow a year ago. So far here's what I have..... Koni Yellow shocks with adjustable rebound. Factory A-spec springs (maybe 20% stiffer than stock, barely noticable) 24mm rear swaybar that's adjustable 28mm front swaybar that's adjustable 255/40 high performance summer tires on stock 17" rims. I know I need more spring but this is a daily driver semi-luxury car so I'm not willing to go any further on spring rates. That's why I compromised with larger swaybars than I would normally get. I realize too big is a problem but since this is a daily driven car I figure the compromise is worth it. Right now handling is pretty balanced. It has slight understeer wtih my foot barely on the throttle and will rotate the tail if I lift. I have some 13" Wilwoods on the way. Engine mods are not an option. I'm not sure what else to do besides going with some stickier tires which is very likely. I need to compete with some co-worker's BMWs, a Cayenne, Cayman, WRX, and a Scion. I'm a bit worried about the Cayman but the owner is not a car guy and I'm hoping I can out drive him. It's very hard for me to get used to this FWD platform, it goes against everything I've learned over the years. I have to think about what to do when it slides rather than it being natural like the GN. Maybe some practice will help. These guys are some of the biggest trash talkers and I would never hear the end of it if I didn't place well.